      serializer_related_field = PrimaryKeyRelatedField
      serializer_url_field = HyperlinkedIdentityField
      serializer_choice_field = ChoiceField
  
      # Default `create` and `update` behavior...
  
      def create(self, validated_data):
          """
          We have a bit of extra checking around this in order to provide
          descriptive messages when something goes wrong, but this method is
 
</s> remove             extra_kwargs[api_settings.URL_FIELD_NAME] = kwargs
 </s> add             extra_kwargs[self.url_field_name] = kwargs </s> remove             kwargs = extra_kwargs.get(api_settings.URL_FIELD_NAME, {})
 </s> add             kwargs = extra_kwargs.get(self.url_field_name, {}) </s> remove             extra_kwargs[api_settings.URL_FIELD_NAME] = kwargs
 </s> add             extra_kwargs[self.url_field_name] = kwargs </s> remove             kwargs = extra_kwargs.get(api_settings.URL_FIELD_NAME, {})
 </s> add             kwargs = extra_kwargs.get(self.url_field_name, {})
    # The field name for hyperlinked identity fields. Defaults to 'url'.
    # You can modify this using the API setting.
    #
    # Note that if you instead need modify this on a per-serializer basis,
    # you'll also need to ensure you update the `create` method on any generic
    # views, to correctly handle the 'Location' response header for
    # "HTTP 201 Created" responses.
    url_field_name = api_settings.URL_FIELD_NAME
      serializer_related_field = PrimaryKeyRelatedField
      serializer_url_field = HyperlinkedIdentityField
      serializer_choice_field = ChoiceField
  
    # The field name for hyperlinked identity fields. Defaults to 'url'.
    # You can modify this using the API setting.
    #
    # Note that if you instead need modify this on a per-serializer basis,
    # you'll also need to ensure you update the `create` method on any generic
    # views, to correctly handle the 'Location' response header for
    # "HTTP 201 Created" responses.
    url_field_name = api_settings.URL_FIELD_NAME
  
      def create(self, validated_data):
          """
          We have a bit of extra checking around this in order to provide
          descriptive messages when something goes wrong, but this method is
keep keep keep keep replace keep keep keep keep keep
 Added url_field_name class attribute to ModelSerializer. Closes #3106. 
rest_framework/serializers.py