public static function humanize($bytes, $base = 1024)
    {
        if (empty($bytes)) {
            return '0 B';
        }
        $class = min((int)log($bytes, $base), count(static::$siPrefix) - 1);

        return sprintf('%1.2F %s', $bytes / pow($base, $class), static::$siPrefix[$class]);
    }