@classmethod
def get_api_sub_resources(cls):
    """Define the API sub-resources this object will appear under.

        This should return a list of API sub-resources that the object
        will be exposed under.

        This is used by the standard attr extensions to discover which
        sub-resources need to be extended with the standard attr fields
        (e.g. created_at/updated_at/etc).
        """
    try:
        return cls.api_sub_resources
    except AttributeError:
        return []
