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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def register(self, entity, url_func):
 """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