$one = substr(str_shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), -5);
    $two = substr(str_shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), -5);
    $three = substr(str_shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), -5);
    $four = substr(str_shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), -5);
    $key = "$one-$two-$three-$four";
    echo $key;