So after we switched to #Python 3.14 in #Fedora Rawhide, the compose is blocked by https://github.com/osbuild/osbuild/issues/2109 thus likely no Python 3.14 as python3 in the repositories yet.
Looks like a breaking change in configparser with no depreciation period, no mention in What's New, non-actionable exception, and no much recent discussion either 😞 https://github.com/python/cpython/issues/65697#issuecomment-2964520637