The only other thing I found
really weird about datetime is how Python 2 had no implementation of a UTC tzinfo class, despite this being utterly trivial -
Huh? it is either so trivial that there is no point -- simiply say that your datetimes are UTC, and you are done.
Or it's not the least bit trivial -- the only difference between a UTC datetime and a "naive" datetime is that one can be converted to (or interact with) other time zones. Except that, as we know from this conversation, is very, very non-trivial!
(Also, technically, UTC would use leap-seconds...)