<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang=""> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>django.db.models.options — Django 1.8.19 documentation</title> <link rel="stylesheet" href="../../../../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../../../../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../../../../', VERSION: '1.8.19', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="../../../../_static/jquery.js"></script> <script type="text/javascript" src="../../../../_static/underscore.js"></script> <script type="text/javascript" src="../../../../_static/doctools.js"></script> <link rel="index" title="Index" href="../../../../genindex.html" /> <link rel="search" 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id="_modules-django-db-models-options"> <h1>Source code for django.db.models.options</h1><div class="highlight"><pre> <span></span><span class="kn">from</span> <span class="nn">__future__</span> <span class="k">import</span> <span class="n">unicode_literals</span> <span class="kn">import</span> <span class="nn">warnings</span> <span class="kn">from</span> <span class="nn">bisect</span> <span class="k">import</span> <span class="n">bisect</span> <span class="kn">from</span> <span class="nn">collections</span> <span class="k">import</span> <span class="n">OrderedDict</span><span class="p">,</span> <span class="n">defaultdict</span> <span class="kn">from</span> <span class="nn">itertools</span> <span class="k">import</span> <span class="n">chain</span> <span class="kn">from</span> <span class="nn">django.apps</span> <span class="k">import</span> <span class="n">apps</span> <span class="kn">from</span> <span class="nn">django.conf</span> <span class="k">import</span> <span class="n">settings</span> <span class="kn">from</span> <span class="nn">django.core.exceptions</span> <span class="k">import</span> <span class="n">FieldDoesNotExist</span> <span class="kn">from</span> <span class="nn">django.db.models.fields</span> <span class="k">import</span> <span class="n">AutoField</span> <span class="kn">from</span> <span class="nn">django.db.models.fields.proxy</span> <span class="k">import</span> <span class="n">OrderWrt</span> <span class="kn">from</span> <span class="nn">django.db.models.fields.related</span> <span class="k">import</span> <span class="n">ManyToManyField</span> <span class="kn">from</span> <span class="nn">django.utils</span> <span class="k">import</span> <span class="n">six</span> <span class="kn">from</span> <span class="nn">django.utils.datastructures</span> <span class="k">import</span> <span class="n">ImmutableList</span><span class="p">,</span> <span class="n">OrderedSet</span> <span class="kn">from</span> <span class="nn">django.utils.deprecation</span> <span class="k">import</span> <span class="n">RemovedInDjango110Warning</span> <span class="kn">from</span> <span class="nn">django.utils.encoding</span> <span class="k">import</span> <span class="p">(</span> <span class="n">force_text</span><span class="p">,</span> <span class="n">python_2_unicode_compatible</span><span class="p">,</span> <span class="n">smart_text</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.utils.functional</span> <span class="k">import</span> <span class="n">cached_property</span> <span class="kn">from</span> <span class="nn">django.utils.lru_cache</span> <span class="k">import</span> <span class="n">lru_cache</span> <span class="kn">from</span> <span class="nn">django.utils.text</span> <span class="k">import</span> <span class="n">camel_case_to_spaces</span> <span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="k">import</span> <span class="n">override</span><span class="p">,</span> <span class="n">string_concat</span> <span class="n">PROXY_PARENTS</span> <span class="o">=</span> <span class="nb">object</span><span class="p">()</span> <span class="n">EMPTY_RELATION_TREE</span> <span class="o">=</span> <span class="nb">tuple</span><span class="p">()</span> <span class="n">IMMUTABLE_WARNING</span> <span class="o">=</span> <span class="p">(</span> <span class="s2">"The return type of '</span><span class="si">%s</span><span class="s2">' should never be mutated. If you want to manipulate this list "</span> <span class="s2">"for your own use, make a copy first."</span> <span class="p">)</span> <span class="n">DEFAULT_NAMES</span> <span class="o">=</span> <span class="p">(</span><span class="s1">'verbose_name'</span><span class="p">,</span> <span class="s1">'verbose_name_plural'</span><span class="p">,</span> <span class="s1">'db_table'</span><span class="p">,</span> <span class="s1">'ordering'</span><span class="p">,</span> <span class="s1">'unique_together'</span><span class="p">,</span> <span class="s1">'permissions'</span><span class="p">,</span> <span class="s1">'get_latest_by'</span><span class="p">,</span> <span class="s1">'order_with_respect_to'</span><span class="p">,</span> <span class="s1">'app_label'</span><span class="p">,</span> <span class="s1">'db_tablespace'</span><span class="p">,</span> <span class="s1">'abstract'</span><span class="p">,</span> <span class="s1">'managed'</span><span class="p">,</span> <span class="s1">'proxy'</span><span class="p">,</span> <span class="s1">'swappable'</span><span class="p">,</span> <span class="s1">'auto_created'</span><span class="p">,</span> <span class="s1">'index_together'</span><span class="p">,</span> <span class="s1">'apps'</span><span class="p">,</span> <span class="s1">'default_permissions'</span><span class="p">,</span> <span class="s1">'select_on_save'</span><span class="p">,</span> <span class="s1">'default_related_name'</span><span class="p">)</span> <span class="k">class</span> <span class="nc">raise_deprecation</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">suggested_alternative</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">suggested_alternative</span> <span class="o">=</span> <span class="n">suggested_alternative</span> <span class="k">def</span> <span class="nf">__call__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">fn</span><span class="p">):</span> <span class="k">def</span> <span class="nf">wrapper</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2"> is an unofficial API that has been deprecated. "</span> <span class="s2">"You may be able to replace it with '</span><span class="si">%s</span><span class="s2">'"</span> <span class="o">%</span> <span class="p">(</span> <span class="n">fn</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">suggested_alternative</span><span class="p">,</span> <span class="p">),</span> <span class="n">RemovedInDjango110Warning</span><span class="p">,</span> <span class="n">stacklevel</span><span class="o">=</span><span class="mi">2</span> <span class="p">)</span> <span class="k">return</span> <span class="n">fn</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">return</span> <span class="n">wrapper</span> <span class="k">def</span> <span class="nf">normalize_together</span><span class="p">(</span><span class="n">option_together</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> option_together can be either a tuple of tuples, or a single</span> <span class="sd"> tuple of two strings. Normalize it to a tuple of tuples, so that</span> <span class="sd"> calling code can uniformly expect that.</span> <span class="sd"> """</span> <span class="k">try</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">option_together</span><span class="p">:</span> <span class="k">return</span> <span class="p">()</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">option_together</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">)):</span> <span class="k">raise</span> <span class="ne">TypeError</span> <span class="n">first_element</span> <span class="o">=</span> <span class="nb">next</span><span class="p">(</span><span class="nb">iter</span><span class="p">(</span><span class="n">option_together</span><span class="p">))</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">first_element</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">)):</span> <span class="n">option_together</span> <span class="o">=</span> <span class="p">(</span><span class="n">option_together</span><span class="p">,)</span> <span class="c1"># Normalize everything to tuples</span> <span class="k">return</span> <span class="nb">tuple</span><span class="p">(</span><span class="nb">tuple</span><span class="p">(</span><span class="n">ot</span><span class="p">)</span> <span class="k">for</span> <span class="n">ot</span> <span class="ow">in</span> <span class="n">option_together</span><span class="p">)</span> <span class="k">except</span> <span class="ne">TypeError</span><span class="p">:</span> <span class="c1"># If the value of option_together isn't valid, return it</span> <span class="c1"># verbatim; this will be picked up by the check framework later.</span> <span class="k">return</span> <span class="n">option_together</span> <span class="k">def</span> <span class="nf">make_immutable_fields_list</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span> <span class="k">return</span> <span class="n">ImmutableList</span><span class="p">(</span><span class="n">data</span><span class="p">,</span> <span class="n">warning</span><span class="o">=</span><span class="n">IMMUTABLE_WARNING</span> <span class="o">%</span> <span class="n">name</span><span class="p">)</span> <span class="nd">@python_2_unicode_compatible</span> <div class="viewcode-block" id="Options"><a class="viewcode-back" href="../../../../ref/models/meta.html#django.db.models.options.Options">[docs]</a><span class="k">class</span> <span class="nc">Options</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="n">FORWARD_PROPERTIES</span> <span class="o">=</span> <span class="p">(</span><span class="s1">'fields'</span><span class="p">,</span> <span class="s1">'many_to_many'</span><span class="p">,</span> <span class="s1">'concrete_fields'</span><span class="p">,</span> <span class="s1">'local_concrete_fields'</span><span class="p">,</span> <span class="s1">'_forward_fields_map'</span><span class="p">)</span> <span class="n">REVERSE_PROPERTIES</span> <span class="o">=</span> <span class="p">(</span><span class="s1">'related_objects'</span><span class="p">,</span> <span class="s1">'fields_map'</span><span class="p">,</span> <span class="s1">'_relation_tree'</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">meta</span><span class="p">,</span> <span class="n">app_label</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields_cache</span> <span class="o">=</span> <span class="p">{}</span> <span class="bp">self</span><span class="o">.</span><span class="n">proxied_children</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_many_to_many</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">virtual_fields</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_name</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name_plural</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_table</span> <span class="o">=</span> <span class="s1">''</span> <span class="bp">self</span><span class="o">.</span><span class="n">ordering</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">unique_together</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">index_together</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">select_on_save</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">default_permissions</span> <span class="o">=</span> <span class="p">(</span><span class="s1">'add'</span><span class="p">,</span> <span class="s1">'change'</span><span class="p">,</span> <span class="s1">'delete'</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">permissions</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">object_name</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">app_label</span> <span class="o">=</span> <span class="n">app_label</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_latest_by</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_tablespace</span> <span class="o">=</span> <span class="n">settings</span><span class="o">.</span><span class="n">DEFAULT_TABLESPACE</span> <span class="bp">self</span><span class="o">.</span><span class="n">meta</span> <span class="o">=</span> <span class="n">meta</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">has_auto_field</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">auto_field</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">abstract</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">managed</span> <span class="o">=</span> <span class="kc">True</span> <span class="bp">self</span><span class="o">.</span><span class="n">proxy</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># For any class that is a proxy (including automatically created</span> <span class="c1"># classes for deferred object loading), proxy_for_model tells us</span> <span class="c1"># which class this model is proxying. Note that proxy_for_model</span> <span class="c1"># can create a chain of proxy models. For non-proxy models, the</span> <span class="c1"># variable is always None.</span> <span class="bp">self</span><span class="o">.</span><span class="n">proxy_for_model</span> <span class="o">=</span> <span class="kc">None</span> <span class="c1"># For any non-abstract class, the concrete class is the model</span> <span class="c1"># in the end of the proxy_for_model chain. In particular, for</span> <span class="c1"># concrete models, the concrete_model is always the class itself.</span> <span class="bp">self</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">swappable</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span> <span class="o">=</span> <span class="n">OrderedDict</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">auto_created</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># To handle various inheritance situations, we need to track where</span> <span class="c1"># managers came from (concrete or abstract base classes). `managers`</span> <span class="c1"># keeps a list of 3-tuples of the form:</span> <span class="c1"># (creation_counter, instance, abstract(=True))</span> <span class="bp">self</span><span class="o">.</span><span class="n">managers</span> <span class="o">=</span> <span class="p">[]</span> <span class="c1"># List of all lookups defined in ForeignKey 'limit_choices_to' options</span> <span class="c1"># from *other* models. Needed for some admin checks. Internal use only.</span> <span class="bp">self</span><span class="o">.</span><span class="n">related_fkey_lookups</span> <span class="o">=</span> <span class="p">[]</span> <span class="c1"># A custom app registry to use, if you're making a separate model set.</span> <span class="bp">self</span><span class="o">.</span><span class="n">apps</span> <span class="o">=</span> <span class="n">apps</span> <span class="bp">self</span><span class="o">.</span><span class="n">default_related_name</span> <span class="o">=</span> <span class="kc">None</span> <span class="nd">@lru_cache</span><span class="p">(</span><span class="n">maxsize</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_map_model</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">link</span><span class="p">):</span> <span class="c1"># This helper function is used to allow backwards compatibility with</span> <span class="c1"># the previous API. No future methods should use this function.</span> <span class="c1"># It maps a field to (field, model or related_model,) depending on the</span> <span class="c1"># field type.</span> <span class="n">model</span> <span class="o">=</span> <span class="n">link</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="k">if</span> <span class="n">model</span> <span class="ow">is</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">:</span> <span class="n">model</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">return</span> <span class="n">link</span><span class="p">,</span> <span class="n">model</span> <span class="nd">@lru_cache</span><span class="p">(</span><span class="n">maxsize</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_map_model_details</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">link</span><span class="p">):</span> <span class="c1"># This helper function is used to allow backwards compatibility with</span> <span class="c1"># the previous API. No future methods should use this function.</span> <span class="c1"># This function maps a field to a tuple of:</span> <span class="c1"># (field, model or related_model, direct, is_m2m) depending on the</span> <span class="c1"># field type.</span> <span class="n">direct</span> <span class="o">=</span> <span class="ow">not</span> <span class="n">link</span><span class="o">.</span><span class="n">auto_created</span> <span class="ow">or</span> <span class="n">link</span><span class="o">.</span><span class="n">concrete</span> <span class="n">model</span> <span class="o">=</span> <span class="n">link</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="k">if</span> <span class="n">model</span> <span class="ow">is</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">:</span> <span class="n">model</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">m2m</span> <span class="o">=</span> <span class="n">link</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">link</span><span class="o">.</span><span class="n">many_to_many</span> <span class="k">return</span> <span class="n">link</span><span class="p">,</span> <span class="n">model</span><span class="p">,</span> <span class="n">direct</span><span class="p">,</span> <span class="n">m2m</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">app_config</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># Don't go through get_app_config to avoid triggering imports.</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">apps</span><span class="o">.</span><span class="n">app_configs</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">app_label</span><span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">installed</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">app_config</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">abstract_managers</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span> <span class="p">(</span><span class="n">counter</span><span class="p">,</span> <span class="n">instance</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">instance</span><span class="p">)</span> <span class="k">for</span> <span class="n">counter</span><span class="p">,</span> <span class="n">instance</span><span class="p">,</span> <span class="n">abstract</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">managers</span> <span class="k">if</span> <span class="n">abstract</span> <span class="p">]</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">concrete_managers</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span> <span class="p">(</span><span class="n">counter</span><span class="p">,</span> <span class="n">instance</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">instance</span><span class="p">)</span> <span class="k">for</span> <span class="n">counter</span><span class="p">,</span> <span class="n">instance</span><span class="p">,</span> <span class="n">abstract</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">managers</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">abstract</span> <span class="p">]</span> <span class="k">def</span> <span class="nf">contribute_to_class</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span> <span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">connection</span> <span class="kn">from</span> <span class="nn">django.db.backends.utils</span> <span class="k">import</span> <span class="n">truncate_name</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="o">=</span> <span class="bp">self</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="n">cls</span> <span class="c1"># First, construct the default values for these options.</span> <span class="bp">self</span><span class="o">.</span><span class="n">object_name</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_name</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="o">.</span><span class="n">lower</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name</span> <span class="o">=</span> <span class="n">camel_case_to_spaces</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">)</span> <span class="c1"># Store the original user-defined values for each option,</span> <span class="c1"># for use when serializing the model definition</span> <span class="bp">self</span><span class="o">.</span><span class="n">original_attrs</span> <span class="o">=</span> <span class="p">{}</span> <span class="c1"># Next, apply any overridden values from 'class Meta'.</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">meta</span><span class="p">:</span> <span class="n">meta_attrs</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">meta</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span> <span class="k">for</span> <span class="n">name</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">meta</span><span class="o">.</span><span class="n">__dict__</span><span class="p">:</span> <span class="c1"># Ignore any private attributes that Django doesn't care about.</span> <span class="c1"># NOTE: We can't modify a dictionary's contents while looping</span> <span class="c1"># over it, so we loop over the *original* dictionary instead.</span> <span class="k">if</span> <span class="n">name</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s1">'_'</span><span class="p">):</span> <span class="k">del</span> <span class="n">meta_attrs</span><span class="p">[</span><span class="n">name</span><span class="p">]</span> <span class="k">for</span> <span class="n">attr_name</span> <span class="ow">in</span> <span class="n">DEFAULT_NAMES</span><span class="p">:</span> <span class="k">if</span> <span class="n">attr_name</span> <span class="ow">in</span> <span class="n">meta_attrs</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">,</span> <span class="n">meta_attrs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">attr_name</span><span class="p">))</span> <span class="bp">self</span><span class="o">.</span><span class="n">original_attrs</span><span class="p">[</span><span class="n">attr_name</span><span class="p">]</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">)</span> <span class="k">elif</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">meta</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">,</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">meta</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">))</span> <span class="bp">self</span><span class="o">.</span><span class="n">original_attrs</span><span class="p">[</span><span class="n">attr_name</span><span class="p">]</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">)</span> <span class="n">ut</span> <span class="o">=</span> <span class="n">meta_attrs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s1">'unique_together'</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">unique_together</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">unique_together</span> <span class="o">=</span> <span class="n">normalize_together</span><span class="p">(</span><span class="n">ut</span><span class="p">)</span> <span class="n">it</span> <span class="o">=</span> <span class="n">meta_attrs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s1">'index_together'</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">index_together</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">index_together</span> <span class="o">=</span> <span class="n">normalize_together</span><span class="p">(</span><span class="n">it</span><span class="p">)</span> <span class="c1"># verbose_name_plural is a special case because it uses a 's'</span> <span class="c1"># by default.</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name_plural</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name_plural</span> <span class="o">=</span> <span class="n">string_concat</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">,</span> <span class="s1">'s'</span><span class="p">)</span> <span class="c1"># Any leftover attributes must be invalid.</span> <span class="k">if</span> <span class="n">meta_attrs</span> <span class="o">!=</span> <span class="p">{}:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"'class Meta' got invalid attribute(s): </span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="s1">','</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">meta_attrs</span><span class="o">.</span><span class="n">keys</span><span class="p">()))</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">verbose_name_plural</span> <span class="o">=</span> <span class="n">string_concat</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">,</span> <span class="s1">'s'</span><span class="p">)</span> <span class="k">del</span> <span class="bp">self</span><span class="o">.</span><span class="n">meta</span> <span class="c1"># If the db_table wasn't provided, use the app_label + model_name.</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_table</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_table</span> <span class="o">=</span> <span class="s2">"</span><span class="si">%s</span><span class="s2">_</span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_name</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_table</span> <span class="o">=</span> <span class="n">truncate_name</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db_table</span><span class="p">,</span> <span class="n">connection</span><span class="o">.</span><span class="n">ops</span><span class="o">.</span><span class="n">max_name_length</span><span class="p">())</span> <span class="k">def</span> <span class="nf">_prepare</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">model</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="p">:</span> <span class="c1"># The app registry will not be ready at this point, so we cannot</span> <span class="c1"># use get_field().</span> <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="k">try</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="o">=</span> <span class="nb">next</span><span class="p">(</span> <span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="n">query</span> <span class="ow">or</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="o">==</span> <span class="n">query</span> <span class="p">)</span> <span class="k">except</span> <span class="ne">StopIteration</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldDoesNotExist</span><span class="p">(</span><span class="s1">'</span><span class="si">%s</span><span class="s1"> has no field named </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">query</span><span class="p">))</span> <span class="bp">self</span><span class="o">.</span><span class="n">ordering</span> <span class="o">=</span> <span class="p">(</span><span class="s1">'_order'</span><span class="p">,)</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">any</span><span class="p">(</span><span class="nb">isinstance</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="n">OrderWrt</span><span class="p">)</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">):</span> <span class="n">model</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="s1">'_order'</span><span class="p">,</span> <span class="n">OrderWrt</span><span class="p">())</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="c1"># Promote the first parent link in lieu of adding yet another</span> <span class="c1"># field.</span> <span class="n">field</span> <span class="o">=</span> <span class="nb">next</span><span class="p">(</span><span class="n">six</span><span class="o">.</span><span class="n">itervalues</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">))</span> <span class="c1"># Look for a local field with the same name as the</span> <span class="c1"># first parent link. If a local field has already been</span> <span class="c1"># created, use it instead of promoting the parent</span> <span class="n">already_created</span> <span class="o">=</span> <span class="p">[</span><span class="n">fld</span> <span class="k">for</span> <span class="n">fld</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span> <span class="k">if</span> <span class="n">fld</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="k">if</span> <span class="n">already_created</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="n">already_created</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="n">field</span><span class="o">.</span><span class="n">primary_key</span> <span class="o">=</span> <span class="kc">True</span> <span class="bp">self</span><span class="o">.</span><span class="n">setup_pk</span><span class="p">(</span><span class="n">field</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">auto</span> <span class="o">=</span> <span class="n">AutoField</span><span class="p">(</span><span class="n">verbose_name</span><span class="o">=</span><span class="s1">'ID'</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">auto_created</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="n">model</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="s1">'id'</span><span class="p">,</span> <span class="n">auto</span><span class="p">)</span> <span class="k">def</span> <span class="nf">add_field</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">,</span> <span class="n">virtual</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="c1"># Insert the given field in the order in which it was created, using</span> <span class="c1"># the "creation_counter" attribute of the field.</span> <span class="c1"># Move many-to-many related fields from self.fields into</span> <span class="c1"># self.many_to_many.</span> <span class="k">if</span> <span class="n">virtual</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">virtual_fields</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">field</span><span class="p">)</span> <span class="k">elif</span> <span class="n">field</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="o">.</span><span class="n">insert</span><span class="p">(</span><span class="n">bisect</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">,</span> <span class="n">field</span><span class="p">),</span> <span class="n">field</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span><span class="o">.</span><span class="n">insert</span><span class="p">(</span><span class="n">bisect</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span><span class="p">,</span> <span class="n">field</span><span class="p">),</span> <span class="n">field</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">setup_pk</span><span class="p">(</span><span class="n">field</span><span class="p">)</span> <span class="c1"># If the field being added is a relation to another known field,</span> <span class="c1"># expire the cache on this field and the forward cache on the field</span> <span class="c1"># being referenced, because there will be new relationships in the</span> <span class="c1"># cache. Otherwise, expire the cache of references *to* this field.</span> <span class="c1"># The mechanism for getting at the related model is slightly odd -</span> <span class="c1"># ideally, we'd just ask for field.related_model. However, related_model</span> <span class="c1"># is a cached property, and all the models haven't been loaded yet, so</span> <span class="c1"># we need to make sure we don't cache a string reference.</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="p">,</span> <span class="s1">'to'</span><span class="p">)</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">_expire_cache</span><span class="p">(</span><span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">pass</span> <span class="bp">self</span><span class="o">.</span><span class="n">_expire_cache</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_expire_cache</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">def</span> <span class="nf">setup_pk</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">primary_key</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="o">=</span> <span class="n">field</span> <span class="n">field</span><span class="o">.</span><span class="n">serialize</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">setup_proxy</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">target</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Does the internal setup so that the current model is a proxy for</span> <span class="sd"> "target".</span> <span class="sd"> """</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="o">=</span> <span class="n">target</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span> <span class="bp">self</span><span class="o">.</span><span class="n">proxy_for_model</span> <span class="o">=</span> <span class="n">target</span> <span class="bp">self</span><span class="o">.</span><span class="n">db_table</span> <span class="o">=</span> <span class="n">target</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">db_table</span> <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s1">'<Options for </span><span class="si">%s</span><span class="s1">>'</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">object_name</span> <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s2">"</span><span class="si">%s</span><span class="s2">.</span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="p">(</span><span class="n">smart_text</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">app_label</span><span class="p">),</span> <span class="n">smart_text</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model_name</span><span class="p">))</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">verbose_name_raw</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> There are a few places where the untranslated verbose name is needed</span> <span class="sd"> (so that we get the same value regardless of currently active</span> <span class="sd"> locale).</span> <span class="sd"> """</span> <span class="k">with</span> <span class="n">override</span><span class="p">(</span><span class="kc">None</span><span class="p">):</span> <span class="k">return</span> <span class="n">force_text</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">swapped</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Has this model been swapped out for another? If so, return the model</span> <span class="sd"> name of the replacement; otherwise, return None.</span> <span class="sd"> For historical reasons, model name lookups using get_model() are</span> <span class="sd"> case insensitive, so we make sure we are case insensitive here.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">swappable</span><span class="p">:</span> <span class="n">model_label</span> <span class="o">=</span> <span class="s1">'</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_name</span><span class="p">)</span> <span class="n">swapped_for</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">settings</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">swappable</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">if</span> <span class="n">swapped_for</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">swapped_label</span><span class="p">,</span> <span class="n">swapped_object</span> <span class="o">=</span> <span class="n">swapped_for</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s1">'.'</span><span class="p">)</span> <span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span> <span class="c1"># setting not in the format app_label.model_name</span> <span class="c1"># raising ImproperlyConfigured here causes problems with</span> <span class="c1"># test cleanup code - instead it is raised in get_user_model</span> <span class="c1"># or as part of validation.</span> <span class="k">return</span> <span class="n">swapped_for</span> <span class="k">if</span> <span class="s1">'</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">swapped_label</span><span class="p">,</span> <span class="n">swapped_object</span><span class="o">.</span><span class="n">lower</span><span class="p">())</span> <span class="ow">not</span> <span class="ow">in</span> <span class="p">(</span><span class="kc">None</span><span class="p">,</span> <span class="n">model_label</span><span class="p">):</span> <span class="k">return</span> <span class="n">swapped_for</span> <span class="k">return</span> <span class="kc">None</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">fields</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of all forward fields on the model and its parents,</span> <span class="sd"> excluding ManyToManyFields.</span> <span class="sd"> Private API intended only to be used by Django itself; get_fields()</span> <span class="sd"> combined with filtering of field properties is the public API for</span> <span class="sd"> obtaining this field list.</span> <span class="sd"> """</span> <span class="c1"># For legacy reasons, the fields property should only contain forward</span> <span class="c1"># fields that are not virtual or with a m2m cardinality. Therefore we</span> <span class="c1"># pass these three filters as filters to the generator.</span> <span class="c1"># The third lambda is a longwinded way of checking f.related_model - we don't</span> <span class="c1"># use that property directly because related_model is a cached property,</span> <span class="c1"># and all the models may not have been loaded yet; we don't want to cache</span> <span class="c1"># the string reference to the related_model.</span> <span class="n">is_not_an_m2m_field</span> <span class="o">=</span> <span class="k">lambda</span> <span class="n">f</span><span class="p">:</span> <span class="ow">not</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">)</span> <span class="n">is_not_a_generic_relation</span> <span class="o">=</span> <span class="k">lambda</span> <span class="n">f</span><span class="p">:</span> <span class="ow">not</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">one_to_many</span><span class="p">)</span> <span class="n">is_not_a_generic_foreign_key</span> <span class="o">=</span> <span class="k">lambda</span> <span class="n">f</span><span class="p">:</span> <span class="ow">not</span> <span class="p">(</span> <span class="n">f</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">many_to_one</span> <span class="ow">and</span> <span class="ow">not</span> <span class="p">(</span><span class="nb">hasattr</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="p">,</span> <span class="s1">'to'</span><span class="p">)</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span> <span class="s2">"fields"</span><span class="p">,</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="n">is_not_an_m2m_field</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="ow">and</span> <span class="n">is_not_a_generic_relation</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="ow">and</span> <span class="n">is_not_a_generic_foreign_key</span><span class="p">(</span><span class="n">f</span><span class="p">))</span> <span class="p">)</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">concrete_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of all concrete fields on the model and its parents.</span> <span class="sd"> Private API intended only to be used by Django itself; get_fields()</span> <span class="sd"> combined with filtering of field properties is the public API for</span> <span class="sd"> obtaining this field list.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span> <span class="s2">"concrete_fields"</span><span class="p">,</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">concrete</span><span class="p">)</span> <span class="p">)</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">local_concrete_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of all concrete fields on the model.</span> <span class="sd"> Private API intended only to be used by Django itself; get_fields()</span> <span class="sd"> combined with filtering of field properties is the public API for</span> <span class="sd"> obtaining this field list.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span> <span class="s2">"local_concrete_fields"</span><span class="p">,</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">concrete</span><span class="p">)</span> <span class="p">)</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_fields_with_model</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">_map_model</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_fields</span><span class="p">()]</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_concrete_fields_with_model</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">_map_model</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">]</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">many_to_many</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of all many to many fields on the model and its parents.</span> <span class="sd"> Private API intended only to be used by Django itself; get_fields()</span> <span class="sd"> combined with filtering of field properties is the public API for</span> <span class="sd"> obtaining this list.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span> <span class="s2">"many_to_many"</span><span class="p">,</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">)</span> <span class="p">)</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">related_objects</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns all related objects pointing to the current model. The related</span> <span class="sd"> objects can come from a one-to-one, one-to-many, or many-to-many field</span> <span class="sd"> relation type.</span> <span class="sd"> Private API intended only to be used by Django itself; get_fields()</span> <span class="sd"> combined with filtering of field properties is the public API for</span> <span class="sd"> obtaining this field list.</span> <span class="sd"> """</span> <span class="n">all_related_fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">return</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span> <span class="s2">"related_objects"</span><span class="p">,</span> <span class="p">(</span><span class="n">obj</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">all_related_fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">obj</span><span class="o">.</span><span class="n">hidden</span> <span class="ow">or</span> <span class="n">obj</span><span class="o">.</span><span class="n">field</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">)</span> <span class="p">)</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_m2m_with_model</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">_map_model</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">]</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">_forward_fields_map</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">res</span> <span class="o">=</span> <span class="p">{}</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="n">res</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="c1"># Due to the way Django's internals work, get_field() should also</span> <span class="c1"># be able to fetch a field by attname. In the case of a concrete</span> <span class="c1"># field with relation, includes the *_id name too</span> <span class="k">try</span><span class="p">:</span> <span class="n">res</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">pass</span> <span class="k">return</span> <span class="n">res</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">fields_map</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">res</span> <span class="o">=</span> <span class="p">{}</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="n">res</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="c1"># Due to the way Django's internals work, get_field() should also</span> <span class="c1"># be able to fetch a field by attname. In the case of a concrete</span> <span class="c1"># field with relation, includes the *_id name too</span> <span class="k">try</span><span class="p">:</span> <span class="n">res</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">pass</span> <span class="k">return</span> <span class="n">res</span> <div class="viewcode-block" id="Options.get_field"><a class="viewcode-back" href="../../../../ref/models/meta.html#django.db.models.options.Options.get_field">[docs]</a> <span class="k">def</span> <span class="nf">get_field</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">many_to_many</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a field instance given a field name. The field can be either a</span> <span class="sd"> forward or reverse field, unless many_to_many is specified; if it is,</span> <span class="sd"> only forward fields will be returned.</span> <span class="sd"> The many_to_many argument exists for backwards compatibility reasons;</span> <span class="sd"> it has been deprecated and will be removed in Django 1.10.</span> <span class="sd"> """</span> <span class="n">m2m_in_kwargs</span> <span class="o">=</span> <span class="n">many_to_many</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">m2m_in_kwargs</span><span class="p">:</span> <span class="c1"># Always throw a warning if many_to_many is used regardless of</span> <span class="c1"># whether it alters the return type or not.</span> <span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span> <span class="s2">"The 'many_to_many' argument on get_field() is deprecated; "</span> <span class="s2">"use a filter on field.many_to_many instead."</span><span class="p">,</span> <span class="n">RemovedInDjango110Warning</span> <span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="c1"># In order to avoid premature loading of the relation tree</span> <span class="c1"># (expensive) we prefer checking if the field is a forward field.</span> <span class="n">field</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_forward_fields_map</span><span class="p">[</span><span class="n">field_name</span><span class="p">]</span> <span class="k">if</span> <span class="n">many_to_many</span> <span class="ow">is</span> <span class="kc">False</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">many_to_many</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldDoesNotExist</span><span class="p">(</span> <span class="s1">'</span><span class="si">%s</span><span class="s1"> has no field named </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">field_name</span><span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">field</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="c1"># If the app registry is not ready, reverse fields are</span> <span class="c1"># unavailable, therefore we throw a FieldDoesNotExist exception.</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">apps</span><span class="o">.</span><span class="n">models_ready</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldDoesNotExist</span><span class="p">(</span> <span class="s2">"</span><span class="si">%s</span><span class="s2"> has no field named </span><span class="si">%r</span><span class="s2">. The app cache isn't ready yet, "</span> <span class="s2">"so if this is an auto-created related field, it won't "</span> <span class="s2">"be available yet."</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">field_name</span><span class="p">)</span> <span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="k">if</span> <span class="n">m2m_in_kwargs</span><span class="p">:</span> <span class="c1"># Previous API does not allow searching reverse fields.</span> <span class="k">raise</span> <span class="n">FieldDoesNotExist</span><span class="p">(</span><span class="s1">'</span><span class="si">%s</span><span class="s1"> has no field named </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">field_name</span><span class="p">))</span> <span class="c1"># Retrieve field instance by name from cached or just-computed</span> <span class="c1"># field map.</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">fields_map</span><span class="p">[</span><span class="n">field_name</span><span class="p">]</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldDoesNotExist</span><span class="p">(</span><span class="s1">'</span><span class="si">%s</span><span class="s1"> has no field named </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">field_name</span><span class="p">))</span></div> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_field()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_field_by_name</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_map_model_details</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">name</span><span class="p">))</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_all_field_names</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">names</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_fields</span><span class="p">()</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="c1"># For backwards compatibility GenericForeignKey should not be</span> <span class="c1"># included in the results.</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">many_to_one</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">related_model</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">continue</span> <span class="c1"># Relations to child proxy models should not be included.</span> <span class="k">if</span> <span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">model</span> <span class="o">!=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">concrete_model</span><span class="p">):</span> <span class="k">continue</span> <span class="n">names</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">)</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="s1">'attname'</span><span class="p">):</span> <span class="n">names</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="n">names</span><span class="p">)</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_all_related_objects</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">local_only</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_proxy_eq</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="n">include_parents</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">if</span> <span class="n">local_only</span> <span class="ow">is</span> <span class="kc">False</span> <span class="k">else</span> <span class="n">PROXY_PARENTS</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span> <span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="n">include_parents</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="n">include_hidden</span><span class="p">,</span> <span class="p">)</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">obj</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">obj</span><span class="o">.</span><span class="n">field</span><span class="p">,</span> <span class="n">ManyToManyField</span><span class="p">))</span> <span class="k">if</span> <span class="n">include_proxy_eq</span><span class="p">:</span> <span class="n">children</span> <span class="o">=</span> <span class="n">chain</span><span class="o">.</span><span class="n">from_iterable</span><span class="p">(</span><span class="n">c</span><span class="o">.</span><span class="n">_relation_tree</span> <span class="k">for</span> <span class="n">c</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">concrete_model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxied_children</span> <span class="k">if</span> <span class="n">c</span> <span class="ow">is</span> <span class="ow">not</span> <span class="bp">self</span><span class="p">)</span> <span class="n">relations</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">children</span> <span class="k">if</span> <span class="n">include_hidden</span> <span class="ow">or</span> <span class="ow">not</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">is_hidden</span><span class="p">())</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">chain</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="n">relations</span><span class="p">)</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_all_related_objects_with_model</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">local_only</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_proxy_eq</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span> <span class="bp">self</span><span class="o">.</span><span class="n">_map_model</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_all_related_objects</span><span class="p">(</span> <span class="n">local_only</span><span class="o">=</span><span class="n">local_only</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="n">include_hidden</span><span class="p">,</span> <span class="n">include_proxy_eq</span><span class="o">=</span><span class="n">include_proxy_eq</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_all_related_many_to_many_objects</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">local_only</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="n">include_parents</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">if</span> <span class="n">local_only</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">True</span> <span class="k">else</span> <span class="n">PROXY_PARENTS</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span> <span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="n">include_parents</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">True</span> <span class="p">)</span> <span class="k">return</span> <span class="p">[</span><span class="n">obj</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">obj</span><span class="o">.</span><span class="n">field</span><span class="p">,</span> <span class="n">ManyToManyField</span><span class="p">)]</span> <span class="nd">@raise_deprecation</span><span class="p">(</span><span class="n">suggested_alternative</span><span class="o">=</span><span class="s2">"get_fields()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_all_related_m2m_objects_with_model</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">forward</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">return</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">_map_model</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">obj</span><span class="o">.</span><span class="n">field</span><span class="p">,</span> <span class="n">ManyToManyField</span><span class="p">)]</span> <span class="k">def</span> <span class="nf">get_base_chain</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">model</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of parent classes leading to 'model' (order from closet</span> <span class="sd"> to most distant ancestor). This has to handle the case were 'model' is</span> <span class="sd"> a grandparent or even more distant relation.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="k">return</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">model</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="k">return</span> <span class="p">[</span><span class="n">model</span><span class="p">]</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="n">res</span> <span class="o">=</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_base_chain</span><span class="p">(</span><span class="n">model</span><span class="p">)</span> <span class="k">if</span> <span class="n">res</span><span class="p">:</span> <span class="n">res</span><span class="o">.</span><span class="n">insert</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="n">parent</span><span class="p">)</span> <span class="k">return</span> <span class="n">res</span> <span class="k">return</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">get_parent_list</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns all the ancestors of this model as a list ordered by MRO.</span> <span class="sd"> Useful for determining if something is an ancestor, regardless of lineage.</span> <span class="sd"> """</span> <span class="n">result</span> <span class="o">=</span> <span class="n">OrderedSet</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">)</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="k">for</span> <span class="n">ancestor</span> <span class="ow">in</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">():</span> <span class="n">result</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">ancestor</span><span class="p">)</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="n">result</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_ancestor_link</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">ancestor</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the field on the current model which points to the given</span> <span class="sd"> "ancestor". This is possible an indirect link (a pointer to a parent</span> <span class="sd"> model, which points, eventually, to the ancestor). Used when</span> <span class="sd"> constructing table joins for model inheritance.</span> <span class="sd"> Returns None if the model isn't an ancestor of this one.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">ancestor</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">[</span><span class="n">ancestor</span><span class="p">]</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="c1"># Tries to get a link field from the immediate parent</span> <span class="n">parent_link</span> <span class="o">=</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_ancestor_link</span><span class="p">(</span><span class="n">ancestor</span><span class="p">)</span> <span class="k">if</span> <span class="n">parent_link</span><span class="p">:</span> <span class="c1"># In case of a proxied model, the first link</span> <span class="c1"># of the chain to the ancestor is that parent</span> <span class="c1"># links</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">[</span><span class="n">parent</span><span class="p">]</span> <span class="ow">or</span> <span class="n">parent_link</span> <span class="k">def</span> <span class="nf">_populate_directed_relation_graph</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> This method is used by each model to find its reverse objects. As this</span> <span class="sd"> method is very expensive and is accessed frequently (it looks up every</span> <span class="sd"> field in a model, in every app), it is computed on first access and then</span> <span class="sd"> is set as a property on every model.</span> <span class="sd"> """</span> <span class="n">related_objects_graph</span> <span class="o">=</span> <span class="n">defaultdict</span><span class="p">(</span><span class="nb">list</span><span class="p">)</span> <span class="n">all_models</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">apps</span><span class="o">.</span><span class="n">get_models</span><span class="p">(</span><span class="n">include_auto_created</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">for</span> <span class="n">model</span> <span class="ow">in</span> <span class="n">all_models</span><span class="p">:</span> <span class="c1"># Abstract model's fields are copied to child models, hence we will</span> <span class="c1"># see the fields from the child models.</span> <span class="k">if</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="k">continue</span> <span class="n">fields_with_relations</span> <span class="o">=</span> <span class="p">(</span> <span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">is_relation</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">related_model</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields_with_relations</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="n">six</span><span class="o">.</span><span class="n">string_types</span><span class="p">):</span> <span class="n">related_objects_graph</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="o">.</span><span class="n">_meta</span><span class="p">]</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">model</span> <span class="ow">in</span> <span class="n">all_models</span><span class="p">:</span> <span class="c1"># Set the relation_tree using the internal __dict__. In this way</span> <span class="c1"># we avoid calling the cached property. In attribute lookup,</span> <span class="c1"># __dict__ takes precedence over a data descriptor (such as</span> <span class="c1"># @cached_property). This means that the _meta._relation_tree is</span> <span class="c1"># only called if related_objects is not in __dict__.</span> <span class="n">related_objects</span> <span class="o">=</span> <span class="n">related_objects_graph</span><span class="p">[</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="p">]</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="s1">'_relation_tree'</span><span class="p">]</span> <span class="o">=</span> <span class="n">related_objects</span> <span class="c1"># It seems it is possible that self is not in all_models, so guard</span> <span class="c1"># against that with default for get().</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s1">'_relation_tree'</span><span class="p">,</span> <span class="n">EMPTY_RELATION_TREE</span><span class="p">)</span> <span class="nd">@cached_property</span> <span class="k">def</span> <span class="nf">_relation_tree</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_populate_directed_relation_graph</span><span class="p">()</span> <span class="k">def</span> <span class="nf">_expire_cache</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">forward</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">):</span> <span class="c1"># This method is usually called by apps.cache_clear(), when the</span> <span class="c1"># registry is finalized, or when a new field is added.</span> <span class="n">properties_to_expire</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="n">forward</span><span class="p">:</span> <span class="n">properties_to_expire</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">FORWARD_PROPERTIES</span><span class="p">)</span> <span class="k">if</span> <span class="n">reverse</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="n">properties_to_expire</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">REVERSE_PROPERTIES</span><span class="p">)</span> <span class="k">for</span> <span class="n">cache_key</span> <span class="ow">in</span> <span class="n">properties_to_expire</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="nb">delattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cache_key</span><span class="p">)</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">pass</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields_cache</span> <span class="o">=</span> <span class="p">{}</span> <div class="viewcode-block" id="Options.get_fields"><a class="viewcode-back" href="../../../../ref/models/meta.html#django.db.models.options.Options.get_fields">[docs]</a> <span class="k">def</span> <span class="nf">get_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of fields associated to the model. By default, includes</span> <span class="sd"> forward and reverse fields, fields derived from inheritance, but not</span> <span class="sd"> hidden fields. The returned fields can be changed using the parameters:</span> <span class="sd"> - include_parents: include fields derived from inheritance</span> <span class="sd"> - include_hidden: include fields that have a related_name that</span> <span class="sd"> starts with a "+"</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">include_parents</span> <span class="ow">is</span> <span class="kc">False</span><span class="p">:</span> <span class="n">include_parents</span> <span class="o">=</span> <span class="n">PROXY_PARENTS</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">include_parents</span><span class="o">=</span><span class="n">include_parents</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="n">include_hidden</span><span class="p">)</span></div> <span class="k">def</span> <span class="nf">_get_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">forward</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">seen_models</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Internal helper function to return fields of the model.</span> <span class="sd"> * If forward=True, then fields defined on this model are returned.</span> <span class="sd"> * If reverse=True, then relations pointing to this model are returned.</span> <span class="sd"> * If include_hidden=True, then fields with is_hidden=True are returned.</span> <span class="sd"> * The include_parents argument toggles if fields from parent models</span> <span class="sd"> should be included. It has three values: True, False, and</span> <span class="sd"> PROXY_PARENTS. When set to PROXY_PARENTS, the call will return all</span> <span class="sd"> fields defined for the current model or any of its parents in the</span> <span class="sd"> parent chain to the model's concrete model.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">include_parents</span> <span class="ow">not</span> <span class="ow">in</span> <span class="p">(</span><span class="kc">True</span><span class="p">,</span> <span class="kc">False</span><span class="p">,</span> <span class="n">PROXY_PARENTS</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Invalid argument for include_parents: </span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="p">(</span><span class="n">include_parents</span><span class="p">,))</span> <span class="c1"># This helper function is used to allow recursion in ``get_fields()``</span> <span class="c1"># implementation and to provide a fast way for Django's internals to</span> <span class="c1"># access specific subsets of fields.</span> <span class="c1"># We must keep track of which models we have already seen. Otherwise we</span> <span class="c1"># could include the same field multiple times from different models.</span> <span class="n">topmost_call</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">if</span> <span class="n">seen_models</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">seen_models</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="n">topmost_call</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">seen_models</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">)</span> <span class="c1"># Creates a cache key composed of all arguments</span> <span class="n">cache_key</span> <span class="o">=</span> <span class="p">(</span><span class="n">forward</span><span class="p">,</span> <span class="n">reverse</span><span class="p">,</span> <span class="n">include_parents</span><span class="p">,</span> <span class="n">include_hidden</span><span class="p">,</span> <span class="n">topmost_call</span><span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="c1"># In order to avoid list manipulation. Always return a shallow copy</span> <span class="c1"># of the results.</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields_cache</span><span class="p">[</span><span class="n">cache_key</span><span class="p">]</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="k">pass</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">[]</span> <span class="c1"># Recursively call _get_fields() on each parent, with the same</span> <span class="c1"># options provided in this call.</span> <span class="k">if</span> <span class="n">include_parents</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">False</span><span class="p">:</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="c1"># In diamond inheritance it is possible that we see the same</span> <span class="c1"># model from two different routes. In that case, avoid adding</span> <span class="c1"># fields from the same parent again.</span> <span class="k">if</span> <span class="n">parent</span> <span class="ow">in</span> <span class="n">seen_models</span><span class="p">:</span> <span class="k">continue</span> <span class="k">if</span> <span class="p">(</span><span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">!=</span> <span class="bp">self</span><span class="o">.</span><span class="n">concrete_model</span> <span class="ow">and</span> <span class="n">include_parents</span> <span class="o">==</span> <span class="n">PROXY_PARENTS</span><span class="p">):</span> <span class="k">continue</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span> <span class="n">forward</span><span class="o">=</span><span class="n">forward</span><span class="p">,</span> <span class="n">reverse</span><span class="o">=</span><span class="n">reverse</span><span class="p">,</span> <span class="n">include_parents</span><span class="o">=</span><span class="n">include_parents</span><span class="p">,</span> <span class="n">include_hidden</span><span class="o">=</span><span class="n">include_hidden</span><span class="p">,</span> <span class="n">seen_models</span><span class="o">=</span><span class="n">seen_models</span><span class="p">):</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="s1">'parent_link'</span><span class="p">)</span> <span class="ow">and</span> <span class="n">obj</span><span class="o">.</span><span class="n">parent_link</span><span class="p">:</span> <span class="k">continue</span> <span class="n">fields</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span> <span class="k">if</span> <span class="n">reverse</span><span class="p">:</span> <span class="c1"># Tree is computed once and cached until the app cache is expired.</span> <span class="c1"># It is composed of a list of fields pointing to the current model</span> <span class="c1"># from other models.</span> <span class="n">all_fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_relation_tree</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">all_fields</span><span class="p">:</span> <span class="c1"># If hidden fields should be included or the relation is not</span> <span class="c1"># intentionally hidden, add to the fields dict.</span> <span class="k">if</span> <span class="n">include_hidden</span> <span class="ow">or</span> <span class="ow">not</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">hidden</span><span class="p">:</span> <span class="n">fields</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="p">)</span> <span class="k">if</span> <span class="n">forward</span><span class="p">:</span> <span class="n">fields</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span> <span class="n">field</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">chain</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">local_fields</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">)</span> <span class="p">)</span> <span class="c1"># Virtual fields are recopied to each child model, and they get a</span> <span class="c1"># different model as field.model in each child. Hence we have to</span> <span class="c1"># add the virtual fields separately from the topmost call. If we</span> <span class="c1"># did this recursively similar to local_fields, we would get field</span> <span class="c1"># instances with field.model != self.model.</span> <span class="k">if</span> <span class="n">topmost_call</span><span class="p">:</span> <span class="n">fields</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span> <span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">virtual_fields</span> <span class="p">)</span> <span class="c1"># In order to avoid list manipulation. Always</span> <span class="c1"># return a shallow copy of the results</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">make_immutable_fields_list</span><span class="p">(</span><span class="s2">"get_fields()"</span><span class="p">,</span> <span class="n">fields</span><span class="p">)</span> <span class="c1"># Store result into cache for later access</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_fields_cache</span><span class="p">[</span><span class="n">cache_key</span><span class="p">]</span> <span class="o">=</span> <span class="n">fields</span> <span class="k">return</span> <span class="n">fields</span></div> </pre></div> </div> </div> </div> <div class="yui-b" id="sidebar"> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h3>Browse</h3> <ul> </ul> <h3>You are here:</h3> <ul> <li> <a href="../../../../index.html">Django 1.8.19 documentation</a> <ul><li><a href="../../../index.html">Module code</a> <ul><li><a href="../../../django.html">django</a> <ul><li>django.db.models.options</li></ul> </li></ul></li></ul> </li> </ul> <div id="searchbox" style="display: none" role="search"> <h3>Quick search</h3> <form class="search" action="../../../../search.html" method="get"> <div><input type="text" name="q" /></div> <div><input type="submit" value="Go" /></div> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <script type="text/javascript">$('#searchbox').show(0);</script> </div> </div> <h3>Last update:</h3> <p class="topless">Mar 10, 2018</p> </div> </div> <div id="ft"> <div class="nav"> <a href="../../../index.html" title="Module code" accesskey="U">up</a></div> </div> </div> <div class="clearer"></div> </div> </body> </html>