Explain what the following piece of code does:

$`$timescale lns $/$ lps

module Mysteryl $($Al$,$ A$0,$ Bl$,$ B$0,$X$,$Y$,$Z$)$;

input Al$,$A$0,$Bl$,$B$0$;

output X$,$Y$,$Z;

wire W$1,$W$2,$W$3,$W$4,$W$5,$W$6,$W$7$;

or $($X$,$W$1,$W$2,$W$3)$;

nor $($Y$,$X$,$Z$)$;

and $($Z$,$W$4,$W$5)$;

and $($W$1,$W$6,$B$1)$;

and $($W$2,$W$6,$W$7,$B$0)$;

and $($W$3,$W$7,$B$0,$B$1)$;

not $($W$6,$A$1)$;

not $($W$7,$A$0)$;

xnor $($W$4,$A$1,$B$1)$;

xnor $($W$5,$A$0,$B$0)$;

endmodule

$```$