uuid personal

function uuid($personal=false){
    if (!$personal) {
        $uuid = random_bytes(16);
    } else {
        $uuid = md5(uniqid().$personal, true);
    }
    $uuid[6] = chr(ord($uuid[6]) & 0x0f | 0x40);
    $uuid[8] = chr(ord($uuid[8]) & 0x3f | 0x80);

    return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($uuid), 4));
}

uuid('admin');