public static function time(string $time = 'now', string $format = null): \DateTimeInterface {
        $timezone = new \DateTimeZone('utc');

        if (is_null($format)) {
            $date = new \DateTime($time, $timezone);
        } else {
            $date = \DateTime::createFromFormat($format, $time, $timezone);
        }

        return $date;
    }