Abseil
From charlesreid1
Abseil is a common library of utilities for C++ and Python that contains useful code from Google's internal code base that has been open-sourced.
Github org: https://github.com/abseil
Blog post announcing Abseil: https://opensource.googleblog.com/2017/09/introducing-abseil-new-common-libraries.html
The Python library, abseil-py, can be installed like this:
$ pip install abseil-py
This contains some useful argument-parsing functionality. It's not documented, though. :(