Creating unique combinations from lists

["Martin v. Löwis"]

> The main emphasis was to show that there was a pattern unfolding that
> should have been translated into more pythonic code than just
> hard-coding nested loops.

Practicality beats purity. That you would solve a more general problem
in a more general way doesn't mean that you shouldn't solve the more
specific problem (combinations from three sets) in a specific,
easy-to-read way. Readability counts.

I find your solution (with nested generators) *very* unpythonic. It
is much more complicated than necessary to solve the problem at hand,
and it doesn't get Pythonic just by using the latest language features.
It may be a smart solution, but not a Pythonic one.

Regards,
Martin

P.S. To solve the general problem, I like

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/496807