python3-six was once useful during the Python2->3 migration but should now be removed.
The dependency could still be there and be totally useless or it could also be a telltale sign that something is not right: development has moved to a new repository and the watch file is outdated; or development has stalled and has been picked up by a fork. Or the Debian maintainer is somewhat MIA.
how pyupgrade does this
pyupgrade also do a lot of other things that might not be desired (rewrite f-strings...)
https://github.com/asottile/pyupgrade?tab=readme-ov-file#remove-six-compatibility-code
packages sorted by popcon
Let's start with the most used packages.
https://salsa.debian.org/detiste-guest/python3-six-removal
Tagged bugs
To tag a new bug:
bts user python3-six@packages.debian.org , usertag 1000959 python3-six-removal
See also: Python/Dead Batteries