https://gerrit.wikimedia.org/r/#/c/432977/ ( cergen.git )
And from https://integration.wikimedia.org/ci/job/cergen-tox-docker/27/console
/usr/lib/python2.7/distutils/dist.py:267: UserWarning: Unknown distribution option: 'python_requires'
Not totally sure what is happening here. This library is Python 3 only, perhaps the python2.7 tox Docker image is not compatible? Not sure.