  
          if self.opts.view_name is None:
              self.opts.view_name = self._get_default_view_name(self.opts.model)
  
          if 'url' not in fields:
              url_field = self._hyperlink_identify_field_class(
                  view_name=self.opts.view_name,
                  lookup_field=self.opts.lookup_field
              )
              ret = self._dict_class()
 
</s> remove             ret['url'] = url_field
 </s> add             ret[self.opts.url_field_name] = url_field </s> remove             return data.get('url', None)
 </s> add             return data.get(self.opts.url_field_name, None)
        if self.opts.url_field_name not in fields:
  
          if self.opts.view_name is None:
              self.opts.view_name = self._get_default_view_name(self.opts.model)
  
        if self.opts.url_field_name not in fields:
              url_field = self._hyperlink_identify_field_class(
                  view_name=self.opts.view_name,
                  lookup_field=self.opts.lookup_field
              )
              ret = self._dict_class()
keep keep keep keep replace keep keep keep keep keep
 Make HyperlinkedModelSerializer `url` field name customizable 
rest_framework/serializers.py