How to use the djangochannelsrestframework.consumers.APIConsumerMetaclass function in djangochannelsrestframework

def bind_to_model(self, model_cls: Type[Model]) -> ModelObserver:
        observer = ModelObserver(func=self.func, model_cls=model_cls)
        observer.groups(self._group_names)
        observer.serializer(self._serializer)
        return observer

    def groups(self, func):
        self._group_names = func
        return self

    def serializer(self, func):
        self._serializer = func
        return self


class ObserverAPIConsumerMetaclass(APIConsumerMetaclass):
    def __new__(mcs, name, bases, body) -> Type[GenericAsyncAPIConsumer]:

        queryset = body.get("queryset", None)
        if queryset is not None:
            for attr_name, attr in body.items():
                if isinstance(attr, _GenericModelObserver):
                    body[attr_name] = attr.bind_to_model(model_cls=queryset.model)
            for base in bases:
                for attr_name in dir(base):
                    attr = getattr(base, attr_name)
                    if isinstance(attr, _GenericModelObserver):
                        body[attr_name] = attr.bind_to_model(model_cls=queryset.model)

        return super().__new__(mcs, name, bases, body)