Comment 1 for bug 1837673

I forgot to mention two potential hurdles:

1. python-acme needs to be updated before backporting python-certbot. This needs to be done anyway by November though as described at https://bugs.launchpad.net/ubuntu/+source/python-acme/+bug/1836823.
2. One potential problem for Xenial is that the version of the python-certbot-doc package in Cosmic built from this python-certbot package requires Sphinx >= 1.6 which is not available in Xenial. If continuing to offer this python-certbot-doc package on Xenial is important, I can probably suggest how to change the upstream code in this package to keep the docs building with the old version of Sphinx.