title: How to filter serializers.SlugRelatedField queryset using model field
body: <p>I am having trouble filtering the possible options for a SlugRelatedField using the <code>queryset</code> parameter.  Here is my serializer</p>
  
  <pre><code>class AttendeeProfileSerializer(serializers.HyperlinkedModelSerializer):
      """
      Profile Serializer
      """
      user = serializers.SlugRelatedField(slug_field='username', queryset=User.objects.all())
      module = serializers.SlugRelatedField(slug_field='id', queryset=AttendeeModule.objects.all())
      picture = serializers.ImageField(allow_empty_file=False, required=False)
  
      class Meta:
          model = AttendeeProfile
          fields = (
              'user', 'module', 'title', 'company', 'email', 'picture', 'is_active', 'created'
          )
  </code></pre>
  
  <p>I would like to filter the module field though, a la <code>serializers.SlugRelatedField(slug_field='id', queryset=AttendeeModule.objects.filter(module__app='module__app')</code> or something similar where each module belongs to an app. </p>
  
  <p>I imagine I need to provide more context to the serializer through the view?  Should I be overriding a method on the view?  I've tried but I'm still new to Django rest framework and it's giving me a lot of trouble</p>
  
  <p>The view is</p>
  
  <pre><code>class AttendeesList(generics.ListCreateAPIView):
      """
  
      """
      queryset = AttendeeProfile.objects.all()
      serializer_class = AttendeeProfileSerializer
  </code></pre>
  
  <p>And using this route</p>
  
  <pre><code>url(r'^apps/(?P&lt;url_name&gt;[a-z][a-z0-9]+)/modules/(?P&lt;module_id&gt;[0-9]+)/attendees$',
      views.AttendeesList.as_view(),
      name='attendees-list'),
  </code></pre>