@classmethod
def get_polymorphic_model_for_type(cls, obj_type):
    """
        Return the polymorphic model associated with the given type.
        Raise `NotImplementedError` if no model is found for the given type. This usually
        means that a serializer is missing in the class's `polymorphic_serializers` attribute.
        """
    return cls.get_polymorphic_model_for_serializer(cls.
        get_polymorphic_serializer_for_type(obj_type))
