def __FindIndex(self, index):
    """Finds an existing index by definition.

    Args:
      definition: entity_pb.CompositeIndex

    Returns:
      entity_pb.CompositeIndex, if it exists; otherwise None
    """
    app = index.app_id()
    self.__ValidateAppId(app)
    if self.__indexes in app:
      for stored_index in self.__indexes[app]:
        if index.definition() == stored_index.definition():
          return stored_index

    return None
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/api/datastore_file_stub.py/DatastoreFileStub.__FindIndex/swapped operands of `in`