          if serializer.is_valid():
              self.object = serializer.object
              self.object.save()
              return Response(serializer.data, status=status.HTTP_201_CREATED)
          return Response(serializer.error_data, status=status.HTTP_400_BAD_REQUEST)
  
  
  class ListModelMixin(object):
      """
      List a queryset.
 
</s> remove 
        form_instance = OnTheFlyForm(self.view.get_serializer().data)
 </s> add         if object:
            data = serializer.data
        form_instance = OnTheFlyForm(data) </s> remove         for k, v in self.view.get_serializer().fields.items():
 </s> add         object, data = None, None
        if hasattr(self.view, 'object'):
            object = self.view.object
        serializer = self.view.get_serializer(instance=object)
        for k, v in serializer.fields.items():
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
          if serializer.is_valid():
              self.object = serializer.object
              self.object.save()
              return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
  
  
  class ListModelMixin(object):
      """
      List a queryset.
keep keep keep keep replace keep keep keep keep keep
 `error_data` -> `errors`
Prefill form for instance view. 
djangorestframework/mixins.py