      # 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
  
      # Default `create` and `update` behavior...
      def create(self, validated_data):
          """
          We have a bit of extra checking around this in order to provide
 
</s> remove         if self.format is None:
 </s> add         if output_format is None: </s> remove         if self.format is None:
 </s> add         output_format = getattr(self, 'format', api_settings.TIME_FORMAT)

        if output_format is None: </s> remove         if self.use_url:
 </s> add         if use_url: </s> remove         self.use_url = kwargs.pop('use_url', self.use_url)
 </s> add         if 'use_url' in kwargs:
            self.use_url = kwargs.pop('use_url')
    url_field_name = None
      # 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 = None
  
      # Default `create` and `update` behavior...
      def create(self, validated_data):
          """
          We have a bit of extra checking around this in order to provide
keep keep keep keep replace keep keep keep keep keep
 Access settings lazily, not at module import 
rest_framework/serializers.py