This helps you understand the cryptic assertion error output from
pytest. For some reason pytest-clarity is a pre-release package so
we need to install it in pipenv with --pre.
The latter is a fork that hasn't been updated since 2016 and the
original still seems to be well maintained, with recent database
updates as well as tests for Python 3.7.
Also, pycountry supports ISO 3166-2 (administrative zones), which
we could eventually use for sub regions.