old_contents: from rest_framework import serializers
  from rest_framework.reverse import reverse
  
  from pages import fields, mixins, models
  from pages.utils import build_url
  
  
  class PageSerializer(serializers.HyperlinkedModelSerializer):
      name = serializers.CharField()
      regions = serializers.SerializerMethodField('rendered_regions')
  
      class Meta:
          fields = ('id', 'url', 'name', 'slug', 'regions')
          model = models.Page
          view_name = 'pages:page-detail'
          extra_kwargs = {
              'url': {'lookup_field': 'slug'},
          }
  
      def rendered_regions(self, obj):
          return obj.rendered_regions(self.context['request'])
  
  
  class JsonPageSerializer(PageSerializer):
      def rendered_regions(self, obj):
          """Render regions as a json-serializable dictionary."""
          return obj.render_json(self.context.get('request'))
  
  
  class GroupSerializer(mixins.LinksMixin, serializers.HyperlinkedModelSerializer):
      url = fields.AbsoluteURLIdentityField()
      pages = serializers.SerializerMethodField('get_pages_link')
  
      links_fields = ['pages']
  
      class Meta:
          model = models.Group
  
      def get_pages_link(self, obj):
          return build_url(
              reverse('pages:page-list', request=self.context.get('request')),
              {'group': obj.slug},
          )
  
new_contents: from rest_framework import serializers
  from rest_framework.reverse import reverse
  
  from pages import fields, mixins, models
  from pages.utils import build_url
  
  
  class PageSerializer(serializers.HyperlinkedModelSerializer):
      name = serializers.CharField()
      regions = serializers.SerializerMethodField('rendered_regions')
  
      class Meta:
          fields = ('id', 'url', 'name', 'slug', 'regions')
          model = models.Page
          view_name = 'pages:page-detail'
          extra_kwargs = {
              'url': {'lookup_field': 'slug', 'view_name': 'pages:page-detail'},
          }
  
      def rendered_regions(self, obj):
          return obj.rendered_regions(self.context['request'])
  
  
  class JsonPageSerializer(PageSerializer):
      def rendered_regions(self, obj):
          """Render regions as a json-serializable dictionary."""
          return obj.render_json(self.context.get('request'))
  
  
  class GroupSerializer(mixins.LinksMixin, serializers.HyperlinkedModelSerializer):
      url = fields.AbsoluteURLIdentityField()
      pages = serializers.SerializerMethodField('get_pages_link')
  
      links_fields = ['pages']
  
      class Meta:
          model = models.Group
  
      def get_pages_link(self, obj):
          return build_url(
              reverse('pages:page-list', request=self.context.get('request')),
              {'group': obj.slug},
          )
  
subject: Add 'view_name' to url extra kwargs