public static function setPermission(array $paths)
    {
        foreach ($paths as $path => $permission) {
            echo "chmod('$path', $permission)...";
            if (is_dir($path) || is_file($path)) {
                try {
                    if (chmod($path, octdec($permission))) {
                        echo "done.\n";
                    };
                } catch (\Exception $e) {
                    echo $e->getMessage() . "\n";
                }
            } else {
                echo "file not found.\n";
            }
        }
    }