The repos which used to send to Python-checkins no longer do so since their
respective migrations (devguide, peps). I don't know who's responsible for
that, so I figured I'd post here.
If people want those back on then that could be arranged. I'm not sure, though, if it still makes sense having emails for every commit from three separate repositories going to the same mailing list.
You can follow the commits through an atom feed, e.g https://github.com/python/peps/commits.atom. That means you could use something like IFTTT on your own to send you an email for each commit so you can track only the repositories you care about. That makes me think that it's worth even less for peps since those all have to be posted here anyway and the devguide doesn't affect people's future production deployments.