There's something magic about compare-locales 3.0. It comes with Python 3 support.
It took me quite a while to get to it, but the writing is on the wall that I had to add support for Python 3. That's just been out for 10 years, too. Well, more like 9ish.
We're testing against Python 2.7, 3.5, and 3.6 now.
Thanks to Emin Mastizada for the reviews of this patch.
Slightly related, we're having two l10n-tooling related proposals out for this year's Google Summer of Code. Check out Google's student guide for how to pick a project. Adrian is mentoring a project to improve the experience of first-time users of Pontoon. I'm mentoring a project to support Android's localization platform as a first-class citizen. You'd write translation quality checks for compare-locales and add support for the XML dialect to Pontoon.