Rosetta: Zebra puzzle (2.)

[Jan van den Broek]

On 2017-05-13, Robert L. <No_spamming at noWhere_7073.org> wrote:

[Schnipp]

> def build_permutations things
>   if block_given?
>     things.permutation.select{|x| yield x}
>   else
>     things.permutation.to_a
>   end
> end

I fail to recognize the Python-version.

-- 
Jan v/d Broek
balglaas at dds.nl