public static function fromASN1ByOID(string $oid, UnspecifiedType $el): self
    {
        if (!array_key_exists($oid, self::MAP_OID_TO_CLASS)) {
            return new UnknownAttributeValue($oid, $el->asElement());
        }
        $cls = self::MAP_OID_TO_CLASS[$oid];
        return $cls::fromASN1($el);
    }