[PATCH] Some Python 3 fixes

[Simon Marchi]

> Sorry for the delay, Simon.

No worries.

> Most of those are on the obvious side
> (print being a function, now, and thus requiring the use of
> parentheses), so they'd be OK to push without approval. The one
> change that is less obvious is the adjustment after itertools.imap
> got replaced by "map"; but the change looks good to me.
> 
> So go ahead and push.

Pushed. Thanks a lot!