protected static function g_create($clazz, $url, $params, $publickey = null, $secretkey = null)
    {
        $resource = call_user_func(array($clazz, 'getInstance'), $clazz, $publickey, $secretkey);
        $result   = $resource->execute($url, self::REQUEST_POST, $resource->getResourceKey(), $params);
        $resource->refresh($result);

        return $resource;
    }