It is little enough code that writing it yourself is likely often much less time-consuming than finding an appropriate solution, much less getting that solution installed. But, I'd have implemented in terms of some useful abstractions that I personally keep at-hand:

use List::Util 'reduce';
use Algorithm::Loops 'MapCarE';

my $prod= reduce {$a+$b} MapCarE { reduce {$a*$b} @_ } \( @x, @y, @z )
+;
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