[Python-Dev] set iteration order

[Hagen Fürstenau]

Hi,

I just hunted down a change in behaviour between Python 3.1 and 3.2 to
possibly changed iteration order of sets due to the optimization in
issue #8685. Of course, this order shouldn't be relied on in the first
place, but the side effect of the optimization might be worth mentioning
in "What's new", maybe also pointing out that the old behaviour can be
simulated with {x for x in a if x not in b} in place of "a-b".

Cheers,
Hagen