def METHOD_NAME(self, entity: Entity | type[Entity], url_func: Callable):
    """Associate a `url_func` with entity's type.
    :param:entity: an :class:`abilian.core.extensions.db.Model` class or
        instance.
    :param:url_func: any callable that accepts an entity instance and
        return an url for it.
    """
    if not inspect.isclass(entity):
        entity = entity.__class__
    assert issubclass(entity, db.Model)
    self._map[entity.entity_type] = url_func