              field.initialize(parent=self, field_name=field_name)
              try:
                  field.field_from_native(data, files, field_name, reverted_data)
              except ValidationError as err:
                  self._errors[field_name] = list(err.messages)
  
          return reverted_data
  
      def perform_validation(self, attrs):
          """
 
</s> remove 
 </s> add             
    def save(self):
        """
        Save the deserialized object and return it.
        """
        self._save() </s> remove     def save(self):
        """
        Save the deserialized object and return it.
        """
 </s> add     def _save(self, parent=None, fk_field=None):
        if parent and fk_field:
            setattr(self.object, fk_field, parent) </s> remove                 setattr(self.object, accessor_name, object_list)
 </s> add                 if isinstance(object_list, ModelSerializer):
                    fk_field = self.object._meta.get_field_by_name(accessor_name)[0].field.name
                    object_list._save(parent=self.object, fk_field=fk_field)
                else:
                    setattr(self.object, accessor_name, object_list) </s> remove class BaseSerializer(Field):
 </s> add class BaseSerializer(WritableField):
                if hasattr(err, 'message_dict'):
                    self._errors[field_name] = [err.message_dict]
                else:
                    self._errors[field_name] = list(err.messages)
              field.initialize(parent=self, field_name=field_name)
              try:
                  field.field_from_native(data, files, field_name, reverted_data)
              except ValidationError as err:
                if hasattr(err, 'message_dict'):
                    self._errors[field_name] = [err.message_dict]
                else:
                    self._errors[field_name] = list(err.messages)
  
          return reverted_data
  
      def perform_validation(self, attrs):
          """
keep keep keep keep replace keep keep keep keep keep
 Add nested create for 1to1 reverse relationships 
rest_framework/serializers.py