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<h1>Source code for django.utils.functional</h1><div class="highlight"><pre>
<span></span><span class="kn">import</span> <span class="nn">copy</span>
<span class="kn">import</span> <span class="nn">operator</span>
<span class="kn">import</span> <span class="nn">sys</span>
<span class="kn">import</span> <span class="nn">warnings</span>
<span class="kn">from</span> <span class="nn">functools</span> <span class="k">import</span> <span class="n">wraps</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.deprecation</span> <span class="k">import</span> <span class="n">RemovedInDjango19Warning</span>
<span class="c1"># You can't trivially replace this with `functools.partial` because this binds</span>
<span class="c1"># to classes and returns bound instances, whereas functools.partial (on</span>
<span class="c1"># CPython) is a type and its instances don't bind.</span>
<span class="k">def</span> <span class="nf">curry</span><span class="p">(</span><span class="n">_curried_func</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">def</span> <span class="nf">_curried</span><span class="p">(</span><span class="o">*</span><span class="n">moreargs</span><span class="p">,</span> <span class="o">**</span><span class="n">morekwargs</span><span class="p">):</span>
<span class="k">return</span> <span class="n">_curried_func</span><span class="p">(</span><span class="o">*</span><span class="p">(</span><span class="n">args</span> <span class="o">+</span> <span class="n">moreargs</span><span class="p">),</span> <span class="o">**</span><span class="nb">dict</span><span class="p">(</span><span class="n">kwargs</span><span class="p">,</span> <span class="o">**</span><span class="n">morekwargs</span><span class="p">))</span>
<span class="k">return</span> <span class="n">_curried</span>
<span class="k">def</span> <span class="nf">memoize</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="n">cache</span><span class="p">,</span> <span class="n">num_args</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Wrap a function so that results for any argument tuple are stored in</span>
<span class="sd"> 'cache'. Note that the args to the function must be usable as dictionary</span>
<span class="sd"> keys.</span>
<span class="sd"> Only the first num_args are considered when creating the key.</span>
<span class="sd"> """</span>
<span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span><span class="s2">"memoize wrapper is deprecated and will be removed in "</span>
<span class="s2">"Django 1.9. Use django.utils.lru_cache instead."</span><span class="p">,</span>
<span class="n">RemovedInDjango19Warning</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="nd">@wraps</span><span class="p">(</span><span class="n">func</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="n">mem_args</span> <span class="o">=</span> <span class="n">args</span><span class="p">[:</span><span class="n">num_args</span><span class="p">]</span>
<span class="k">if</span> <span class="n">mem_args</span> <span class="ow">in</span> <span class="n">cache</span><span class="p">:</span>
<span class="k">return</span> <span class="n">cache</span><span class="p">[</span><span class="n">mem_args</span><span class="p">]</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">)</span>
<span class="n">cache</span><span class="p">[</span><span class="n">mem_args</span><span class="p">]</span> <span class="o">=</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">wrapper</span>
<div class="viewcode-block" id="cached_property"><a class="viewcode-back" href="../../../ref/utils.html#django.forms.cached_property">[docs]</a><span class="k">class</span> <span class="nc">cached_property</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Decorator that converts a method with a single self argument into a</span>
<span class="sd"> property cached on the instance.</span>
<span class="sd"> Optional ``name`` argument allows you to make cached properties of other</span>
<span class="sd"> methods. (e.g. url = cached_property(get_absolute_url, name='url') )</span>
<span class="sd"> """</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">func</span><span class="p">,</span> <span class="n">name</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">func</span> <span class="o">=</span> <span class="n">func</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="s1">'__doc__'</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">name</span> <span class="o">=</span> <span class="n">name</span> <span class="ow">or</span> <span class="n">func</span><span class="o">.</span><span class="n">__name__</span>
<span class="k">def</span> <span class="nf">__get__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">instance</span><span class="p">,</span> <span class="nb">type</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
<span class="k">if</span> <span class="n">instance</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
<span class="k">return</span> <span class="bp">self</span>
<span class="n">res</span> <span class="o">=</span> <span class="n">instance</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">func</span><span class="p">(</span><span class="n">instance</span><span class="p">)</span>
<span class="k">return</span> <span class="n">res</span></div>
<span class="k">class</span> <span class="nc">Promise</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> This is just a base class for the proxy class created in</span>
<span class="sd"> the closure of the lazy function. It can be used to recognize</span>
<span class="sd"> promises in code.</span>
<span class="sd"> """</span>
<span class="k">pass</span>
<span class="k">def</span> <span class="nf">lazy</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="o">*</span><span class="n">resultclasses</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Turns any callable into a lazy evaluated callable. You need to give result</span>
<span class="sd"> classes or types -- at least one is needed so that the automatic forcing of</span>
<span class="sd"> the lazy evaluation code is triggered. Results are not memoized; the</span>
<span class="sd"> function is evaluated on every access.</span>
<span class="sd"> """</span>
<span class="nd">@total_ordering</span>
<span class="k">class</span> <span class="nc">__proxy__</span><span class="p">(</span><span class="n">Promise</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Encapsulate a function call and act as a proxy for methods that are</span>
<span class="sd"> called on the result of that function. The function is not evaluated</span>
<span class="sd"> until one of the methods on the result is called.</span>
<span class="sd"> """</span>
<span class="n">__prepared</span> <span class="o">=</span> <span class="kc">False</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">args</span><span class="p">,</span> <span class="n">kw</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__args</span> <span class="o">=</span> <span class="n">args</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__kw</span> <span class="o">=</span> <span class="n">kw</span>
<span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">__prepared</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__prepare_class__</span><span class="p">()</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__prepared</span> <span class="o">=</span> <span class="kc">True</span>
<span class="k">def</span> <span class="nf">__reduce__</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="n">_lazy_proxy_unpickle</span><span class="p">,</span>
<span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">)</span> <span class="o">+</span> <span class="n">resultclasses</span>
<span class="p">)</span>
<span class="nd">@classmethod</span>
<span class="k">def</span> <span class="nf">__prepare_class__</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span>
<span class="k">for</span> <span class="n">resultclass</span> <span class="ow">in</span> <span class="n">resultclasses</span><span class="p">:</span>
<span class="k">for</span> <span class="n">type_</span> <span class="ow">in</span> <span class="n">resultclass</span><span class="o">.</span><span class="n">mro</span><span class="p">():</span>
<span class="k">for</span> <span class="n">method_name</span> <span class="ow">in</span> <span class="n">type_</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">keys</span><span class="p">():</span>
<span class="c1"># All __promise__ return the same wrapper method, they</span>
<span class="c1"># look up the correct implementation when called.</span>
<span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">method_name</span><span class="p">):</span>
<span class="k">continue</span>
<span class="n">meth</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__promise__</span><span class="p">(</span><span class="n">method_name</span><span class="p">)</span>
<span class="nb">setattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">method_name</span><span class="p">,</span> <span class="n">meth</span><span class="p">)</span>
<span class="n">cls</span><span class="o">.</span><span class="n">_delegate_bytes</span> <span class="o">=</span> <span class="nb">bytes</span> <span class="ow">in</span> <span class="n">resultclasses</span>
<span class="n">cls</span><span class="o">.</span><span class="n">_delegate_text</span> <span class="o">=</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span> <span class="ow">in</span> <span class="n">resultclasses</span>
<span class="k">assert</span> <span class="ow">not</span> <span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_delegate_bytes</span> <span class="ow">and</span> <span class="n">cls</span><span class="o">.</span><span class="n">_delegate_text</span><span class="p">),</span> <span class="p">(</span>
<span class="s2">"Cannot call lazy() with both bytes and text return types."</span><span class="p">)</span>
<span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_delegate_text</span><span class="p">:</span>
<span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY3</span><span class="p">:</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__str__</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__text_cast</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__unicode__</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__text_cast</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__str__</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__bytes_cast_encoded</span>
<span class="k">elif</span> <span class="n">cls</span><span class="o">.</span><span class="n">_delegate_bytes</span><span class="p">:</span>
<span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY3</span><span class="p">:</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__bytes__</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__bytes_cast</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__str__</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__bytes_cast</span>
<span class="nd">@classmethod</span>
<span class="k">def</span> <span class="nf">__promise__</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">method_name</span><span class="p">):</span>
<span class="c1"># Builds a wrapper around some magic method</span>
<span class="k">def</span> <span class="nf">__wrapper__</span><span class="p">(</span><span class="bp">self</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">kw</span><span class="p">):</span>
<span class="c1"># Automatically triggers the evaluation of a lazy value and</span>
<span class="c1"># applies the given magic method of the result type.</span>
<span class="n">res</span> <span class="o">=</span> <span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">)</span>
<span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">res</span><span class="p">,</span> <span class="n">method_name</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">kw</span><span class="p">)</span>
<span class="k">return</span> <span class="n">__wrapper__</span>
<span class="k">def</span> <span class="nf">__text_cast</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__bytes_cast</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">bytes</span><span class="p">(</span><span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">))</span>
<span class="k">def</span> <span class="nf">__bytes_cast_encoded</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">)</span><span class="o">.</span><span class="n">encode</span><span class="p">(</span><span class="s1">'utf-8'</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__cast</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_delegate_bytes</span><span class="p">:</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__bytes_cast</span><span class="p">()</span>
<span class="k">elif</span> <span class="bp">self</span><span class="o">.</span><span class="n">_delegate_text</span><span class="p">:</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__text_cast</span><span class="p">()</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">return</span> <span class="n">func</span><span class="p">(</span><span class="o">*</span><span class="bp">self</span><span class="o">.</span><span class="n">__args</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">__kw</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__ne__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">Promise</span><span class="p">):</span>
<span class="n">other</span> <span class="o">=</span> <span class="n">other</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span> <span class="o">!=</span> <span class="n">other</span>
<span class="k">def</span> <span class="nf">__eq__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">Promise</span><span class="p">):</span>
<span class="n">other</span> <span class="o">=</span> <span class="n">other</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span> <span class="o">==</span> <span class="n">other</span>
<span class="k">def</span> <span class="nf">__lt__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">Promise</span><span class="p">):</span>
<span class="n">other</span> <span class="o">=</span> <span class="n">other</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span> <span class="o"><</span> <span class="n">other</span>
<span class="k">def</span> <span class="nf">__hash__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">hash</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__cast</span><span class="p">())</span>
<span class="k">def</span> <span class="nf">__mod__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">rhs</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_delegate_bytes</span> <span class="ow">and</span> <span class="n">six</span><span class="o">.</span><span class="n">PY2</span><span class="p">:</span>
<span class="k">return</span> <span class="nb">bytes</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">%</span> <span class="n">rhs</span>
<span class="k">elif</span> <span class="bp">self</span><span class="o">.</span><span class="n">_delegate_text</span><span class="p">:</span>
<span class="k">return</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">%</span> <span class="n">rhs</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">__cast</span><span class="p">()</span> <span class="o">%</span> <span class="n">rhs</span>
<span class="k">def</span> <span class="nf">__deepcopy__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">memo</span><span class="p">):</span>
<span class="c1"># Instances of this class are effectively immutable. It's just a</span>
<span class="c1"># collection of functions. So we don't need to do anything</span>
<span class="c1"># complicated for copying.</span>
<span class="n">memo</span><span class="p">[</span><span class="nb">id</span><span class="p">(</span><span class="bp">self</span><span class="p">)]</span> <span class="o">=</span> <span class="bp">self</span>
<span class="k">return</span> <span class="bp">self</span>
<span class="nd">@wraps</span><span class="p">(</span><span class="n">func</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">kw</span><span class="p">):</span>
<span class="c1"># Creates the proxy object, instead of the actual value.</span>
<span class="k">return</span> <span class="n">__proxy__</span><span class="p">(</span><span class="n">args</span><span class="p">,</span> <span class="n">kw</span><span class="p">)</span>
<span class="k">return</span> <span class="n">__wrapper__</span>
<span class="k">def</span> <span class="nf">_lazy_proxy_unpickle</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="n">args</span><span class="p">,</span> <span class="n">kwargs</span><span class="p">,</span> <span class="o">*</span><span class="n">resultclasses</span><span class="p">):</span>
<span class="k">return</span> <span class="n">lazy</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="o">*</span><span class="n">resultclasses</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>
<div class="viewcode-block" id="allow_lazy"><a class="viewcode-back" href="../../../ref/utils.html#django.forms.allow_lazy">[docs]</a><span class="k">def</span> <span class="nf">allow_lazy</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="o">*</span><span class="n">resultclasses</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> A decorator that allows a function to be called with one or more lazy</span>
<span class="sd"> arguments. If none of the args are lazy, the function is evaluated</span>
<span class="sd"> immediately, otherwise a __proxy__ is returned that will evaluate the</span>
<span class="sd"> function when needed.</span>
<span class="sd"> """</span>
<span class="n">lazy_func</span> <span class="o">=</span> <span class="n">lazy</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="o">*</span><span class="n">resultclasses</span><span class="p">)</span>
<span class="nd">@wraps</span><span class="p">(</span><span class="n">func</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="k">for</span> <span class="n">arg</span> <span class="ow">in</span> <span class="nb">list</span><span class="p">(</span><span class="n">args</span><span class="p">)</span> <span class="o">+</span> <span class="nb">list</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="n">kwargs</span><span class="p">)):</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">arg</span><span class="p">,</span> <span class="n">Promise</span><span class="p">):</span>
<span class="k">break</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">return</span> <span class="n">func</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">lazy_func</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></div>
<span class="n">empty</span> <span class="o">=</span> <span class="nb">object</span><span class="p">()</span>
<span class="k">def</span> <span class="nf">new_method_proxy</span><span class="p">(</span><span class="n">func</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">inner</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_setup</span><span class="p">()</span>
<span class="k">return</span> <span class="n">func</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">)</span>
<span class="k">return</span> <span class="n">inner</span>
<span class="k">class</span> <span class="nc">LazyObject</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> A wrapper for another class that can be used to delay instantiation of the</span>
<span class="sd"> wrapped class.</span>
<span class="sd"> By subclassing, you have the opportunity to intercept and alter the</span>
<span class="sd"> instantiation. If you don't need to do that, use SimpleLazyObject.</span>
<span class="sd"> """</span>
<span class="c1"># Avoid infinite recursion when tracing __init__ (#19456).</span>
<span class="n">_wrapped</span> <span class="o">=</span> <span class="kc">None</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="c1"># Note: if a subclass overrides __init__(), it will likely need to</span>
<span class="c1"># override __copy__() and __deepcopy__() as well.</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="o">=</span> <span class="n">empty</span>
<span class="n">__getattr__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">getattr</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__setattr__</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="n">value</span><span class="p">):</span>
<span class="k">if</span> <span class="n">name</span> <span class="o">==</span> <span class="s2">"_wrapped"</span><span class="p">:</span>
<span class="c1"># Assign to __dict__ to avoid infinite __setattr__ loops.</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="s2">"_wrapped"</span><span class="p">]</span> <span class="o">=</span> <span class="n">value</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_setup</span><span class="p">()</span>
<span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">value</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__delattr__</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">if</span> <span class="n">name</span> <span class="o">==</span> <span class="s2">"_wrapped"</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"can't delete _wrapped."</span><span class="p">)</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_setup</span><span class="p">()</span>
<span class="nb">delattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,</span> <span class="n">name</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">_setup</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Must be implemented by subclasses to initialize the wrapped object.</span>
<span class="sd"> """</span>
<span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s1">'subclasses of LazyObject must provide a _setup() method'</span><span class="p">)</span>
<span class="c1"># Because we have messed with __class__ below, we confuse pickle as to what</span>
<span class="c1"># class we are pickling. We're going to have to initialize the wrapped</span>
<span class="c1"># object to successfully pickle it, so we might as well just pickle the</span>
<span class="c1"># wrapped object since they're supposed to act the same way.</span>
<span class="c1">#</span>
<span class="c1"># Unfortunately, if we try to simply act like the wrapped object, the ruse</span>
<span class="c1"># will break down when pickle gets our id(). Thus we end up with pickle</span>
<span class="c1"># thinking, in effect, that we are a distinct object from the wrapped</span>
<span class="c1"># object, but with the same __dict__. This can cause problems (see #25389).</span>
<span class="c1">#</span>
<span class="c1"># So instead, we define our own __reduce__ method and custom unpickler. We</span>
<span class="c1"># pickle the wrapped object as the unpickler's argument, so that pickle</span>
<span class="c1"># will pickle it normally, and then the unpickler simply returns its</span>
<span class="c1"># argument.</span>
<span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_setup</span><span class="p">()</span>
<span class="k">return</span> <span class="p">(</span><span class="n">unpickle_lazyobject</span><span class="p">,</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,))</span>
<span class="c1"># We have to explicitly override __getstate__ so that older versions of</span>
<span class="c1"># pickle don't try to pickle the __dict__ (which in the case of a</span>
<span class="c1"># SimpleLazyObject may contain a lambda). The value will end up being</span>
<span class="c1"># ignored by our __reduce__ and custom unpickler.</span>
<span class="k">def</span> <span class="nf">__getstate__</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="k">def</span> <span class="nf">__copy__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="c1"># If uninitialized, copy the wrapper. Use type(self), not</span>
<span class="c1"># self.__class__, because the latter is proxied.</span>
<span class="k">return</span> <span class="nb">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)()</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># If initialized, return a copy of the wrapped object.</span>
<span class="k">return</span> <span class="n">copy</span><span class="o">.</span><span class="n">copy</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__deepcopy__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">memo</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="c1"># We have to use type(self), not self.__class__, because the</span>
<span class="c1"># latter is proxied.</span>
<span class="n">result</span> <span class="o">=</span> <span class="nb">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)()</span>
<span class="n">memo</span><span class="p">[</span><span class="nb">id</span><span class="p">(</span><span class="bp">self</span><span class="p">)]</span> <span class="o">=</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">copy</span><span class="o">.</span><span class="n">deepcopy</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,</span> <span class="n">memo</span><span class="p">)</span>
<span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY3</span><span class="p">:</span>
<span class="n">__bytes__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">bytes</span><span class="p">)</span>
<span class="n">__str__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">str</span><span class="p">)</span>
<span class="n">__bool__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">bool</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">__str__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">str</span><span class="p">)</span>
<span class="n">__unicode__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">unicode</span><span class="p">)</span> <span class="c1"># NOQA: unicode undefined on PY3</span>
<span class="n">__nonzero__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">bool</span><span class="p">)</span>
<span class="c1"># Introspection support</span>
<span class="n">__dir__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">dir</span><span class="p">)</span>
<span class="c1"># Need to pretend to be the wrapped class, for the sake of objects that</span>
<span class="c1"># care about this (especially in equality tests)</span>
<span class="n">__class__</span> <span class="o">=</span> <span class="nb">property</span><span class="p">(</span><span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">attrgetter</span><span class="p">(</span><span class="s2">"__class__"</span><span class="p">)))</span>
<span class="n">__eq__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">eq</span><span class="p">)</span>
<span class="n">__ne__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">ne</span><span class="p">)</span>
<span class="n">__hash__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">hash</span><span class="p">)</span>
<span class="c1"># Dictionary methods support</span>
<span class="n">__getitem__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">getitem</span><span class="p">)</span>
<span class="n">__setitem__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">setitem</span><span class="p">)</span>
<span class="n">__delitem__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">delitem</span><span class="p">)</span>
<span class="n">__len__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="nb">len</span><span class="p">)</span>
<span class="n">__contains__</span> <span class="o">=</span> <span class="n">new_method_proxy</span><span class="p">(</span><span class="n">operator</span><span class="o">.</span><span class="n">contains</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">unpickle_lazyobject</span><span class="p">(</span><span class="n">wrapped</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Used to unpickle lazy objects. Just return its argument, which will be the</span>
<span class="sd"> wrapped object.</span>
<span class="sd"> """</span>
<span class="k">return</span> <span class="n">wrapped</span>
<span class="n">unpickle_lazyobject</span><span class="o">.</span><span class="n">__safe_for_unpickling__</span> <span class="o">=</span> <span class="kc">True</span>
<span class="c1"># Workaround for http://bugs.python.org/issue12370</span>
<span class="n">_super</span> <span class="o">=</span> <span class="nb">super</span>
<span class="k">class</span> <span class="nc">SimpleLazyObject</span><span class="p">(</span><span class="n">LazyObject</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> A lazy object initialized from any function.</span>
<span class="sd"> Designed for compound objects of unknown type. For builtins or objects of</span>
<span class="sd"> known type, use django.utils.functional.lazy.</span>
<span class="sd"> """</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">func</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Pass in a callable that returns the object to be wrapped.</span>
<span class="sd"> If copies are made of the resulting SimpleLazyObject, which can happen</span>
<span class="sd"> in various circumstances within Django, then you must ensure that the</span>
<span class="sd"> callable can be safely run more than once and will return the same</span>
<span class="sd"> value.</span>
<span class="sd"> """</span>
<span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="s1">'_setupfunc'</span><span class="p">]</span> <span class="o">=</span> <span class="n">func</span>
<span class="n">_super</span><span class="p">(</span><span class="n">SimpleLazyObject</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__init__</span><span class="p">()</span>
<span class="k">def</span> <span class="nf">_setup</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_setupfunc</span><span class="p">()</span>
<span class="c1"># Return a meaningful representation of the lazy object for debugging</span>
<span class="c1"># without evaluating the wrapped object.</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">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="n">repr_attr</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_setupfunc</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">repr_attr</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span>
<span class="k">return</span> <span class="s1">'<</span><span class="si">%s</span><span class="s1">: </span><span class="si">%r</span><span class="s1">>'</span> <span class="o">%</span> <span class="p">(</span><span class="nb">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">repr_attr</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__copy__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="c1"># If uninitialized, copy the wrapper. Use SimpleLazyObject, not</span>
<span class="c1"># self.__class__, because the latter is proxied.</span>
<span class="k">return</span> <span class="n">SimpleLazyObject</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_setupfunc</span><span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># If initialized, return a copy of the wrapped object.</span>
<span class="k">return</span> <span class="n">copy</span><span class="o">.</span><span class="n">copy</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">__deepcopy__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">memo</span><span class="p">):</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span> <span class="ow">is</span> <span class="n">empty</span><span class="p">:</span>
<span class="c1"># We have to use SimpleLazyObject, not self.__class__, because the</span>
<span class="c1"># latter is proxied.</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">SimpleLazyObject</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_setupfunc</span><span class="p">)</span>
<span class="n">memo</span><span class="p">[</span><span class="nb">id</span><span class="p">(</span><span class="bp">self</span><span class="p">)]</span> <span class="o">=</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">result</span>
<span class="k">return</span> <span class="n">copy</span><span class="o">.</span><span class="n">deepcopy</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_wrapped</span><span class="p">,</span> <span class="n">memo</span><span class="p">)</span>
<span class="k">class</span> <span class="nc">lazy_property</span><span class="p">(</span><span class="nb">property</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> A property that works with subclasses by wrapping the decorated</span>
<span class="sd"> functions of the base class.</span>
<span class="sd"> """</span>
<span class="k">def</span> <span class="nf">__new__</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">fget</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">fset</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">fdel</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">doc</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
<span class="k">if</span> <span class="n">fget</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span>
<span class="nd">@wraps</span><span class="p">(</span><span class="n">fget</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">fget</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">instance_type</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">fget</span><span class="o">.</span><span class="n">__name__</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">name</span><span class="p">)()</span>
<span class="k">if</span> <span class="n">fset</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span>
<span class="nd">@wraps</span><span class="p">(</span><span class="n">fset</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">fset</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">value</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">fset</span><span class="o">.</span><span class="n">__name__</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">name</span><span class="p">)(</span><span class="n">value</span><span class="p">)</span>
<span class="k">if</span> <span class="n">fdel</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span>
<span class="nd">@wraps</span><span class="p">(</span><span class="n">fdel</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">fdel</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">fdel</span><span class="o">.</span><span class="n">__name__</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">name</span><span class="p">)()</span>
<span class="k">return</span> <span class="nb">property</span><span class="p">(</span><span class="n">fget</span><span class="p">,</span> <span class="n">fset</span><span class="p">,</span> <span class="n">fdel</span><span class="p">,</span> <span class="n">doc</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">partition</span><span class="p">(</span><span class="n">predicate</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Splits the values into two sets, based on the return value of the function</span>
<span class="sd"> (True/False). e.g.:</span>
<span class="sd"> >>> partition(lambda x: x > 3, range(5))</span>
<span class="sd"> [0, 1, 2, 3], [4]</span>
<span class="sd"> """</span>
<span class="n">results</span> <span class="o">=</span> <span class="p">([],</span> <span class="p">[])</span>
<span class="k">for</span> <span class="n">item</span> <span class="ow">in</span> <span class="n">values</span><span class="p">:</span>
<span class="n">results</span><span class="p">[</span><span class="n">predicate</span><span class="p">(</span><span class="n">item</span><span class="p">)]</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">item</span><span class="p">)</span>
<span class="k">return</span> <span class="n">results</span>
<span class="k">if</span> <span class="n">sys</span><span class="o">.</span><span class="n">version_info</span> <span class="o">>=</span> <span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">2</span><span class="p">):</span>
<span class="kn">from</span> <span class="nn">functools</span> <span class="k">import</span> <span class="n">total_ordering</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># For Python < 2.7.2. total_ordering in versions prior to 2.7.2 is buggy.</span>
<span class="c1"># See http://bugs.python.org/issue10042 for details. For these versions use</span>
<span class="c1"># code borrowed from Python 2.7.3.</span>
<span class="k">def</span> <span class="nf">total_ordering</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span>
<span class="sd">"""Class decorator that fills in missing ordering methods"""</span>
<span class="n">convert</span> <span class="o">=</span> <span class="p">{</span>
<span class="s1">'__lt__'</span><span class="p">:</span> <span class="p">[(</span><span class="s1">'__gt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="p">(</span><span class="bp">self</span> <span class="o"><</span> <span class="n">other</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">)),</span>
<span class="p">(</span><span class="s1">'__le__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="bp">self</span> <span class="o"><</span> <span class="n">other</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__ge__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o"><</span> <span class="n">other</span><span class="p">)],</span>
<span class="s1">'__le__'</span><span class="p">:</span> <span class="p">[(</span><span class="s1">'__ge__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o"><=</span> <span class="n">other</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__lt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="bp">self</span> <span class="o"><=</span> <span class="n">other</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__gt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o"><=</span> <span class="n">other</span><span class="p">)],</span>
<span class="s1">'__gt__'</span><span class="p">:</span> <span class="p">[(</span><span class="s1">'__lt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="p">(</span><span class="bp">self</span> <span class="o">></span> <span class="n">other</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">)),</span>
<span class="p">(</span><span class="s1">'__ge__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="bp">self</span> <span class="o">></span> <span class="n">other</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__le__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o">></span> <span class="n">other</span><span class="p">)],</span>
<span class="s1">'__ge__'</span><span class="p">:</span> <span class="p">[(</span><span class="s1">'__le__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="p">(</span><span class="ow">not</span> <span class="bp">self</span> <span class="o">>=</span> <span class="n">other</span><span class="p">)</span> <span class="ow">or</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__gt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="bp">self</span> <span class="o">>=</span> <span class="n">other</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o">==</span> <span class="n">other</span><span class="p">),</span>
<span class="p">(</span><span class="s1">'__lt__'</span><span class="p">,</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">:</span> <span class="ow">not</span> <span class="bp">self</span> <span class="o">>=</span> <span class="n">other</span><span class="p">)]</span>
<span class="p">}</span>
<span class="n">roots</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="nb">dir</span><span class="p">(</span><span class="n">cls</span><span class="p">))</span> <span class="o">&</span> <span class="nb">set</span><span class="p">(</span><span class="n">convert</span><span class="p">)</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">roots</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s1">'must define at least one ordering operation: < > <= >='</span><span class="p">)</span>
<span class="n">root</span> <span class="o">=</span> <span class="nb">max</span><span class="p">(</span><span class="n">roots</span><span class="p">)</span> <span class="c1"># prefer __lt__ to __le__ to __gt__ to __ge__</span>
<span class="k">for</span> <span class="n">opname</span><span class="p">,</span> <span class="n">opfunc</span> <span class="ow">in</span> <span class="n">convert</span><span class="p">[</span><span class="n">root</span><span class="p">]:</span>
<span class="k">if</span> <span class="n">opname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">roots</span><span class="p">:</span>
<span class="n">opfunc</span><span class="o">.</span><span class="n">__name__</span> <span class="o">=</span> <span class="n">opname</span>
<span class="n">opfunc</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="nb">int</span><span class="p">,</span> <span class="n">opname</span><span class="p">)</span><span class="o">.</span><span class="n">__doc__</span>
<span class="nb">setattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">opname</span><span class="p">,</span> <span class="n">opfunc</span><span class="p">)</span>
<span class="k">return</span> <span class="n">cls</span>
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