      def custom_action_with_list_fields(self, request, pk):
          """
          A custom action using both list field and list serializer in the serializer.
          """
          return super(ExampleSerializer, self).retrieve(self, request)
  
      @action(detail=False)
      def custom_list_action(self, request):
          return super(ExampleViewSet, self).list(self, request)
  
 
</s> remove         return super(ExampleSerializer, self).retrieve(self, request)
 </s> add         raise NotImplementedError </s> remove         return super(ExampleSerializer, self).retrieve(self, request)
 </s> add         raise NotImplementedError </s> remove         return super(ExampleViewSet, self).list(self, request)
 </s> add         raise NotImplementedError </s> remove         return super(ExampleViewSet, self).list(self, request)
 </s> add         """Custom description."""
        raise NotImplementedError

    @custom_list_action_multiple_methods.mapping.delete
    def custom_list_action_multiple_methods_delete(self, request):
        """Deletion description."""
        raise NotImplementedError
        raise NotImplementedError
      def custom_action_with_list_fields(self, request, pk):
          """
          A custom action using both list field and list serializer in the serializer.
          """
        raise NotImplementedError
  
      @action(detail=False)
      def custom_list_action(self, request):
          return super(ExampleViewSet, self).list(self, request)
  
keep keep keep keep replace keep keep keep keep keep
 Improvements to ViewSet extra actions (#5605)

* View suffix already set by initializer

* Add 'name' and 'description' attributes to ViewSet

ViewSets may now provide their `name` and `description` attributes
directly, instead of relying on view introspection to derive them.
These attributes may also be provided with the view's initkwargs.

The ViewSet `name` and `suffix` initkwargs are mutually exclusive.

The `action` decorator now provides the `name` and `description` to
the view's initkwargs. By default, these values are derived from the
method name and its docstring. The `name` may be overridden by providing
it as an argument to the decorator.

The `get_view_name` and `get_view_description` hooks now provide the
view instance to the handler, instead of the view class. The default
implementations of these handlers now respect the `name`/`description`.

* Add 'extra actions' to ViewSet & browsable APIs

* Update simple router tests

Removed old test logic around link/action decorators from `v2.3`. Also
simplified the test by making the results explicit instead of computed.

* Add method mapping to ViewSet actions

* Document extra action method mapping 
tests/test_schemas.py