Besides, python list comprehension isn't that far from the mathematical version. Compare:
{ x^2 : x in Z, x^2 > 10 }
with
[ x^2 for x in Z if x^2 > 10 ]
The main problem is that you can't have a list of all positive integers, so you're kind of forced to make it a generator instead. And the standard set notation clashes a bit with the notation of dictionaries, but on the whole it's not that bad.
