def store_many_vectors(self, hash_name, bucket_keys, vs, data):
        """
        Store a batch of vectors.
        Stores vector and JSON-serializable data in bucket with specified key.
        """
        if data is None:
            data = itertools.repeat(data)
        for v, k, d in zip(vs, bucket_keys, data):
            self.store_vector(hash_name, k, v, d)
Store a batch of vectors.
        Stores vector and JSON-serializable data in bucket with specified key.