public static function batch(
        ClientInterface $client,
        $requests,
        array $options = []
    ) {
        $res = [];
        self::cmpCallback($options, 'fulfilled', $res);
        self::cmpCallback($options, 'rejected', $res);
        $pool = new static($client, $requests, $options);
        $pool->promise()->wait();
        ksort($res);

        return $res;
    }