public static function create_list($params = null, $apiKey = null)
    {
        $class = get_class();
        if (!isset($params['trackers']) || !is_array($params['trackers'])) {
            $clone = $params;
            unset($params);
            $params['trackers'] = $clone;
        }

        $requestor = new Requestor($apiKey);
        $url = self::classUrl($class);
        list($response, $apiKey) = $requestor->request('post', $url.'/create_list', $params);
    }