This is needed for newer certbot (the function it was using before will be removed in Python 3.8).
--- distro provides information about the OS distribution it runs on, such as a reliable machine-readable ID, or version information. It is the recommended replacement for Python's original platform.linux_distribution function (which will be removed in Python 3.8). It also provides much more functionality which isn't necessarily Python bound, like a command-line interface. --- OK to import? There is a python 2 version in a separate tree upstream, but I don't propose adding that to ports unless something we want in ports actually starts depending on it.
