The problem here is funny: `Message.as_string()` imports `email.generator` when called.
Now, `email.generator` has been updated to the security update that depends on the new class `HeaderWriteError`. But we already had imported `email.errors` earlier, in either of the `email.charset` or `email.message` imports - so it is still at the old version and does not have the class. ** Also affects: python3.10 (Ubuntu) Importance: Undecided Status: New ** Also affects: python3.8 (Ubuntu) Importance: Undecided Status: New ** Tags added: regression-update -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2080940 Title: unattended-upgrades broken by python-upgrade To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python3.10/+bug/2080940/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs