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  <h1>Source code for django.db.models.manager</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">inspect</span>
<span class="kn">from</span> <span class="nn">importlib</span> <span class="k">import</span> <span class="n">import_module</span>

<span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">router</span>
<span class="kn">from</span> <span class="nn">django.db.models.query</span> <span class="k">import</span> <span class="n">QuerySet</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.encoding</span> <span class="k">import</span> <span class="n">python_2_unicode_compatible</span>


<span class="nd">@python_2_unicode_compatible</span>
<span class="k">class</span> <span class="nc">BaseManager</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
    <span class="c1"># Tracks each time a Manager instance is created. Used to retain order.</span>
    <span class="n">creation_counter</span> <span class="o">=</span> <span class="mi">0</span>

    <span class="c1"># Set to True for the &#39;objects&#39; managers that are automatically created.</span>
    <span class="n">auto_created</span> <span class="o">=</span> <span class="kc">False</span>

    <span class="c1">#: If set to True the manager will be serialized into migrations and will</span>
    <span class="c1">#: thus be available in e.g. RunPython operations</span>
    <span class="n">use_in_migrations</span> <span class="o">=</span> <span class="kc">False</span>

    <span class="k">def</span> <span class="nf">__new__</span><span class="p">(</span><span class="bp">cls</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="c1"># We capture the arguments to make returning them trivial</span>
        <span class="n">obj</span> <span class="o">=</span> <span class="nb">super</span><span class="p">(</span><span class="n">BaseManager</span><span class="p">,</span> <span class="bp">cls</span><span class="p">)</span><span class="o">.</span><span class="fm">__new__</span><span class="p">(</span><span class="bp">cls</span><span class="p">)</span>
        <span class="n">obj</span><span class="o">.</span><span class="n">_constructor_args</span> <span class="o">=</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="k">return</span> <span class="n">obj</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="nb">super</span><span class="p">(</span><span class="n">BaseManager</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_set_creation_counter</span><span class="p">()</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="kc">None</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">name</span> <span class="o">=</span> <span class="kc">None</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="o">=</span> <span class="kc">None</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_hints</span> <span class="o">=</span> <span class="p">{}</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="sd">&quot;&quot;&quot; Return &quot;app_label.model_label.manager_name&quot;. &quot;&quot;&quot;</span>
        <span class="k">return</span> <span class="s1">&#39;</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">&#39;</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</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">label</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="k">def</span> <span class="nf">deconstruct</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Returns a 5-tuple of the form (as_manager (True), manager_class,</span>
<span class="sd">        queryset_class, args, kwargs).</span>

<span class="sd">        Raises a ValueError if the manager is dynamically generated.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="n">qs_class</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_queryset_class</span>
        <span class="k">if</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">&#39;_built_with_as_manager&#39;</span><span class="p">,</span> <span class="kc">False</span><span class="p">):</span>
            <span class="c1"># using MyQuerySet.as_manager()</span>
            <span class="k">return</span> <span class="p">(</span>
                <span class="kc">True</span><span class="p">,</span>  <span class="c1"># as_manager</span>
                <span class="kc">None</span><span class="p">,</span>  <span class="c1"># manager_class</span>
                <span class="s1">&#39;</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">&#39;</span> <span class="o">%</span> <span class="p">(</span><span class="n">qs_class</span><span class="o">.</span><span class="vm">__module__</span><span class="p">,</span> <span class="n">qs_class</span><span class="o">.</span><span class="vm">__name__</span><span class="p">),</span>  <span class="c1"># qs_class</span>
                <span class="kc">None</span><span class="p">,</span>  <span class="c1"># args</span>
                <span class="kc">None</span><span class="p">,</span>  <span class="c1"># kwargs</span>
            <span class="p">)</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">module_name</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="vm">__module__</span>
            <span class="n">name</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="vm">__class__</span><span class="o">.</span><span class="vm">__name__</span>
            <span class="c1"># Make sure it&#39;s actually there and not an inner class</span>
            <span class="n">module</span> <span class="o">=</span> <span class="n">import_module</span><span class="p">(</span><span class="n">module_name</span><span class="p">)</span>
            <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">module</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
                <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span>
                    <span class="s2">&quot;Could not find manager </span><span class="si">%s</span><span class="s2"> in </span><span class="si">%s</span><span class="s2">.</span><span class="se">\n</span><span class="s2">&quot;</span>
                    <span class="s2">&quot;Please note that you need to inherit from managers you &quot;</span>
                    <span class="s2">&quot;dynamically generated with &#39;from_queryset()&#39;.&quot;</span>
                    <span class="o">%</span> <span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">module_name</span><span class="p">)</span>
                <span class="p">)</span>
            <span class="k">return</span> <span class="p">(</span>
                <span class="kc">False</span><span class="p">,</span>  <span class="c1"># as_manager</span>
                <span class="s1">&#39;</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">&#39;</span> <span class="o">%</span> <span class="p">(</span><span class="n">module_name</span><span class="p">,</span> <span class="n">name</span><span class="p">),</span>  <span class="c1"># manager_class</span>
                <span class="kc">None</span><span class="p">,</span>  <span class="c1"># qs_class</span>
                <span class="bp">self</span><span class="o">.</span><span class="n">_constructor_args</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span>  <span class="c1"># args</span>
                <span class="bp">self</span><span class="o">.</span><span class="n">_constructor_args</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span>  <span class="c1"># kwargs</span>
            <span class="p">)</span>

    <span class="k">def</span> <span class="nf">check</span><span class="p">(</span><span class="bp">self</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="p">[]</span>

    <span class="nd">@classmethod</span>
    <span class="k">def</span> <span class="nf">_get_queryset_methods</span><span class="p">(</span><span class="bp">cls</span><span class="p">,</span> <span class="n">queryset_class</span><span class="p">):</span>
        <span class="k">def</span> <span class="nf">create_method</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">method</span><span class="p">):</span>
            <span class="k">def</span> <span class="nf">manager_method</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">kwargs</span><span class="p">):</span>
                <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">get_queryset</span><span class="p">(),</span> <span class="n">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">kwargs</span><span class="p">)</span>
            <span class="n">manager_method</span><span class="o">.</span><span class="vm">__name__</span> <span class="o">=</span> <span class="n">method</span><span class="o">.</span><span class="vm">__name__</span>
            <span class="n">manager_method</span><span class="o">.</span><span class="vm">__doc__</span> <span class="o">=</span> <span class="n">method</span><span class="o">.</span><span class="vm">__doc__</span>
            <span class="k">return</span> <span class="n">manager_method</span>

        <span class="n">new_methods</span> <span class="o">=</span> <span class="p">{}</span>
        <span class="c1"># Refs http://bugs.python.org/issue1785.</span>
        <span class="n">predicate</span> <span class="o">=</span> <span class="n">inspect</span><span class="o">.</span><span class="n">isfunction</span> <span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY3</span> <span class="k">else</span> <span class="n">inspect</span><span class="o">.</span><span class="n">ismethod</span>
        <span class="k">for</span> <span class="n">name</span><span class="p">,</span> <span class="n">method</span> <span class="ow">in</span> <span class="n">inspect</span><span class="o">.</span><span class="n">getmembers</span><span class="p">(</span><span class="n">queryset_class</span><span class="p">,</span> <span class="n">predicate</span><span class="o">=</span><span class="n">predicate</span><span class="p">):</span>
            <span class="c1"># Only copy missing methods.</span>
            <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
                <span class="k">continue</span>
            <span class="c1"># Only copy public methods or methods with the attribute `queryset_only=False`.</span>
            <span class="n">queryset_only</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">method</span><span class="p">,</span> <span class="s1">&#39;queryset_only&#39;</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span>
            <span class="k">if</span> <span class="n">queryset_only</span> <span class="ow">or</span> <span class="p">(</span><span class="n">queryset_only</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">name</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s1">&#39;_&#39;</span><span class="p">)):</span>
                <span class="k">continue</span>
            <span class="c1"># Copy the method onto the manager.</span>
            <span class="n">new_methods</span><span class="p">[</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">create_method</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">method</span><span class="p">)</span>
        <span class="k">return</span> <span class="n">new_methods</span>

    <span class="nd">@classmethod</span>
    <span class="k">def</span> <span class="nf">from_queryset</span><span class="p">(</span><span class="bp">cls</span><span class="p">,</span> <span class="n">queryset_class</span><span class="p">,</span> <span class="n">class_name</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
        <span class="k">if</span> <span class="n">class_name</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
            <span class="n">class_name</span> <span class="o">=</span> <span class="s1">&#39;</span><span class="si">%s</span><span class="s1">From</span><span class="si">%s</span><span class="s1">&#39;</span> <span class="o">%</span> <span class="p">(</span><span class="bp">cls</span><span class="o">.</span><span class="vm">__name__</span><span class="p">,</span> <span class="n">queryset_class</span><span class="o">.</span><span class="vm">__name__</span><span class="p">)</span>
        <span class="n">class_dict</span> <span class="o">=</span> <span class="p">{</span>
            <span class="s1">&#39;_queryset_class&#39;</span><span class="p">:</span> <span class="n">queryset_class</span><span class="p">,</span>
        <span class="p">}</span>
        <span class="n">class_dict</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="bp">cls</span><span class="o">.</span><span class="n">_get_queryset_methods</span><span class="p">(</span><span class="n">queryset_class</span><span class="p">))</span>
        <span class="k">return</span> <span class="nb">type</span><span class="p">(</span><span class="n">class_name</span><span class="p">,</span> <span class="p">(</span><span class="bp">cls</span><span class="p">,),</span> <span class="n">class_dict</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">model</span><span class="p">,</span> <span class="n">name</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">name</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="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="n">model</span>

        <span class="nb">setattr</span><span class="p">(</span><span class="n">model</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">ManagerDescriptor</span><span class="p">(</span><span class="bp">self</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">add_manager</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">_set_creation_counter</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Sets the creation counter value for this instance and increments the</span>
<span class="sd">        class-level copy.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">creation_counter</span> <span class="o">=</span> <span class="n">BaseManager</span><span class="o">.</span><span class="n">creation_counter</span>
        <span class="n">BaseManager</span><span class="o">.</span><span class="n">creation_counter</span> <span class="o">+=</span> <span class="mi">1</span>

    <span class="k">def</span> <span class="nf">db_manager</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">hints</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
        <span class="n">obj</span> <span class="o">=</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="p">)</span>
        <span class="n">obj</span><span class="o">.</span><span class="n">_db</span> <span class="o">=</span> <span class="n">using</span> <span class="ow">or</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span>
        <span class="n">obj</span><span class="o">.</span><span class="n">_hints</span> <span class="o">=</span> <span class="n">hints</span> <span class="ow">or</span> <span class="bp">self</span><span class="o">.</span><span class="n">_hints</span>
        <span class="k">return</span> <span class="n">obj</span>

    <span class="nd">@property</span>
    <span class="k">def</span> <span class="nf">db</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">_db</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_read</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="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span>

    <span class="c1">#######################</span>
    <span class="c1"># PROXIES TO QUERYSET #</span>
    <span class="c1">#######################</span>

    <span class="k">def</span> <span class="nf">get_queryset</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Returns a new QuerySet object.  Subclasses can override this method to</span>
<span class="sd">        easily customize the behavior of the Manager.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_queryset_class</span><span class="p">(</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="p">,</span> <span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_db</span><span class="p">,</span> <span class="n">hints</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">all</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="c1"># We can&#39;t proxy this method through the `QuerySet` like we do for the</span>
        <span class="c1"># rest of the `QuerySet` methods. This is because `QuerySet.all()`</span>
        <span class="c1"># works by creating a &quot;copy&quot; of the current queryset and in making said</span>
        <span class="c1"># copy, all the cached `prefetch_related` lookups are lost. See the</span>
        <span class="c1"># implementation of `RelatedManager.get_queryset()` for a better</span>
        <span class="c1"># understanding of how this comes into play.</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_queryset</span><span class="p">()</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">return</span> <span class="p">(</span>
            <span class="nb">isinstance</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="vm">__class__</span><span class="p">)</span> <span class="ow">and</span>
            <span class="bp">self</span><span class="o">.</span><span class="n">_constructor_args</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="n">_constructor_args</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">return</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="p">)</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">id</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span>


<div class="viewcode-block" id="Manager"><a class="viewcode-back" href="../../../../topics/db/managers.html#django.db.models.Manager">[docs]</a><span class="k">class</span> <span class="nc">Manager</span><span class="p">(</span><span class="n">BaseManager</span><span class="o">.</span><span class="n">from_queryset</span><span class="p">(</span><span class="n">QuerySet</span><span class="p">)):</span>
    <span class="k">pass</span></div>


<span class="k">class</span> <span class="nc">ManagerDescriptor</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">manager</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">manager</span> <span class="o">=</span> <span class="n">manager</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="bp">cls</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="ow">not</span> <span class="kc">None</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">AttributeError</span><span class="p">(</span><span class="s2">&quot;Manager isn&#39;t accessible via </span><span class="si">%s</span><span class="s2"> instances&quot;</span> <span class="o">%</span> <span class="bp">cls</span><span class="o">.</span><span class="vm">__name__</span><span class="p">)</span>

        <span class="k">if</span> <span class="bp">cls</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">raise</span> <span class="ne">AttributeError</span><span class="p">(</span><span class="s2">&quot;Manager isn&#39;t available; </span><span class="si">%s</span><span class="s2"> is abstract&quot;</span> <span class="o">%</span> <span class="p">(</span>
                <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span>
            <span class="p">))</span>

        <span class="k">if</span> <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">AttributeError</span><span class="p">(</span>
                <span class="s2">&quot;Manager isn&#39;t available; &#39;</span><span class="si">%s</span><span class="s2">.</span><span class="si">%s</span><span class="s2">&#39; has been swapped for &#39;</span><span class="si">%s</span><span class="s2">&#39;&quot;</span> <span class="o">%</span> <span class="p">(</span>
                    <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span>
                    <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span>
                    <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">,</span>
                <span class="p">)</span>
            <span class="p">)</span>

        <span class="k">return</span> <span class="bp">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">managers_map</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">manager</span><span class="o">.</span><span class="n">name</span><span class="p">]</span>


<span class="k">class</span> <span class="nc">EmptyManager</span><span class="p">(</span><span class="n">Manager</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">model</span><span class="p">):</span>
        <span class="nb">super</span><span class="p">(</span><span class="n">EmptyManager</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="n">model</span>

    <span class="k">def</span> <span class="nf">get_queryset</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="nb">super</span><span class="p">(</span><span class="n">EmptyManager</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">get_queryset</span><span class="p">()</span><span class="o">.</span><span class="n">none</span><span class="p">()</span>
</pre></div>

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