Of course, this package fails to comply with Debian policy, but that clearly didn't stop the user from being able to install it - which means the data is in the system and we need to be able to cope with it.
I'm not sure if this needs to be fixed in ubuntu-drivers or in python-apt. Reassigning to ubuntu-drivers for the moment.
This issue has been reported on IRC today. The problem seems to trace back to a locally-installed package with a non-utf8 maintainer field:
Package: davmail
Maintainer: Micka�l Guessant <email address hidden>
Of course, this package fails to comply with Debian policy, but that clearly didn't stop the user from being able to install it - which means the data is in the system and we need to be able to cope with it.
I'm not sure if this needs to be fixed in ubuntu-drivers or in python-apt. Reassigning to ubuntu-drivers for the moment.