title: How can i bulk create in django rest serializer
body: <p>I used to use <strong>allow_add_remove=True</strong> which was availabe in django rest 2.0  for writing nestable serializer but its not available in 3.0 and i am having hard time implementing it.</p>
  
  <p>I want to do something like this</p>
  
  <pre><code>class UserSerialzier():
      project = ProjectSerilaizer(many=True, allow_add_remove=True, read_only=False)
  
  
  class ProjectSerialzier():
      ideas = IdeaSerilaizer(many=True, allow_add_remove=True, read_only=False)
      sources = SourceSerilaizer(many=True, allow_add_remove=True, read_only=False)
  
  class IdeaSerialzier():
      pass
  
  class SourceSerialzier():
      pass      
  </code></pre>
  
  <p>Now i am not able to know how can i implement the allow_add_remove behavior in DRF 3.0</p>
  
  <p>I am confused that do i need to override <code>create</code> and <code>update</code> method of UserSerializer</p>
  
  <p>or i need  to create separate IdeaListSerializer  for every model</p>
  
  <pre><code>class IdeaListSerializer(serializers.ListSerializer):
      def create(self, validated_data):
          ideas = [Idea(**item) for item in validated_data]
          return Ideas.objects.bulk_create(books)
  </code></pre>