How to use the djangochannelsrestframework.decorators.action function in djangochannelsrestframework

        @action()
        def test_sync_action(self, pk=None, **kwargs):
            user = self.get_object(pk=pk)

            s = self.get_serializer(
                action_kwargs={'pk': pk},
                instance=user
            )
            return s.data, 200

        @action()
        def test_sync_action(self, pk=None, **kwargs):
            results["test_sync_action"] = pk
            return {"pk": pk, "sync": True}, 200

        @action()
        async def test_async_action(self, pk=None, **kwargs):
            results["test_action"] = pk
            return {"pk": pk}, 200

        @action()
        async def update_username(self, pk=None, name=None, **kwargs):
            tm = await database_sync_to_async(self.get_object)(pk=pk)
            tm.name = name
            await database_sync_to_async(tm.save)()
            return {'pk': pk}, 200

    @action()
    async def unsubscribe_instance(self, request_id=None, **kwargs):
        if request_id is None:
            raise ValueError("request_id must have a value set")
        # subscribe!
        instance = await database_sync_to_async(self.get_object)(**kwargs)
        await self.handle_instance_change.unsubscribe(instance=instance)
        del self.subscribed_requests[self.__class__.handle_instance_change]

        return None, status.HTTP_204_NO_CONTENT

    @action()
    def retrieve(self, **kwargs):
        instance = self.get_object(**kwargs)
        serializer = self.get_serializer(instance=instance, action_kwargs=kwargs)
        return serializer.data, status.HTTP_200_OK

    @action()
    def update(self, data, **kwargs):
        instance = self.get_object(data=data, **kwargs)

        serializer = self.get_serializer(
            instance=instance, data=data, action_kwargs=kwargs, partial=False
        )

        serializer.is_valid(raise_exception=True)
        self.perform_update(serializer, **kwargs)

        if getattr(instance, "_prefetched_objects_cache", None):
            # If 'prefetch_related' has been applied to a queryset, we need to
            # forcibly invalidate the prefetch cache on the instance.
            instance._prefetched_objects_cache = {}

        return serializer.data, status.HTTP_200_OK

    @action()
    def patch(self, data, **kwargs):
        instance = self.get_object(data=data, **kwargs)

        serializer = self.get_serializer(
            instance=instance, data=data, action_kwargs=kwargs, partial=True
        )

        serializer.is_valid(raise_exception=True)
        self.perform_patch(serializer, **kwargs)

        if getattr(instance, "_prefetched_objects_cache", None):
            # If 'prefetch_related' has been applied to a queryset, we need to
            # forcibly invalidate the prefetch cache on the instance.
            instance._prefetched_objects_cache = {}

        return serializer.data, status.HTTP_200_OK

    @action()
    def create(self, data, **kwargs):
        serializer = self.get_serializer(data=data, action_kwargs=kwargs)
        serializer.is_valid(raise_exception=True)
        self.perform_create(serializer, **kwargs)
        return serializer.data, status.HTTP_201_CREATED

    @action()
    def delete(self, **kwargs):
        instance = self.get_object(**kwargs)

        self.perform_delete(instance, **kwargs)
        return None, status.HTTP_204_NO_CONTENT