Hi Matthias, a finding that only one version of python will be supported is very unpleasing. I miss such declaration in both debian wiki python page and Debian Python policy, or its not clearly stated. And this is the first place I found it.
I also miss a guideline for python developers to provide support of several python versions. It is common to use tox and virtualenv to provide support for them, which requires different versions of python interpreters to be installed. I'm also concerned that existence of python3-distutils, and not python3.Y-distutils, will repeatedly break all existing virtualenvs in the system when the python version changes, as we experience now. I hope these concerns have been addressed before the decision to support only one version of python and you can point on documents where I can find further information about how to handle these cases from the point of view of Python developer. Regards, Vlastimil