Switch to Python 3.x (issue 545370043 by address@hidden)

[lemzwerg]

Mhmm, I'm not happy with that.  What I can imagine is to *prefer* Python
3.x over 2.x.

Is there a reason to enforce 3.x?  I thought that all of your recent
work was to ensure that the scripts work both with 2.x and 3.x – am I
missing something?

https://codereview.appspot.com/545370043/