@classmethod
  def DeleteNotifications(cls, urns, end=None, token=None):
    """Delete notifications for given urns."""

    if token is None:
      raise ValueError("token can't be None")

    predicates = [cls.index_format % urn for urn in urns]
    data_store.DB.DeleteAttributes(cls.notification_queue, predicates,
                                   end=end, token=token, sync=True)
dataset/ETHPy150Open google/grr/grr/lib/aff4_objects/collects.py/PackedVersionedCollection.DeleteNotifications/original