def parent_key(self):
    """Get the parent's key.

    This method is useful for avoiding a potential fetch from the datastore
    but still get information about the instances parent.

    Returns:
      Parent key of entity, None if there is no parent.
    """
    if self._parent_key is not None:
      return self._parent_key
    elif self._parent is not None:
      return self._parent.key()
    elif self._entity is not None:
      return self._entity.parent()
    elif self._key is not None:
      return self._key.parent()
    else:
      return None
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/ext/db/__init__.py/Model.parent_key/original