def METHOD_NAME(index_dir):
    assert os.path.exists(os.path.join(
        index_dir, "vector.index")), "vector.index not found ..."
    assert os.path.exists(os.path.join(
        index_dir, "id_map.pkl")), "id_map.pkl not found ... "
    searcher = faiss.read_index(os.path.join(index_dir, "vector.index"))
    with open(os.path.join(index_dir, "id_map.pkl"), "rb") as fd:
        id_map = pickle.load(fd)
    return searcher, id_map