Upgrade fails on python-is-python2 calculation step

[Branimir Lambov]

Appears different from #1875523 as I manually uninstalled both python-gi and python-pyside.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.38
ProcVersionSignature: Ubuntu 4.15.0-118.119-generic 4.15.18
Uname: Linux 4.15.0-118-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.17
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Wed Sep 30 14:35:22 2020
InstallationDate: Installed on 2016-01-28 (1707 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-09-30 (0 days ago)
VarLogDistupgradeAptlog: Log time: 2020-09-30 14:32:20.091574

[Brian Murray (brian-murray)]

What happens if you manually try to run '/usr/lib/update-notifier/update-motd-updates-available'?

[Branimir Lambov (blambov)]

`sudo /usr/lib/update-notifier/update-motd-updates-available` completes with no message, after the first time software update found a sensors package (which may be just a coincidence) but upgrade failed in the same way, with almost identical logs.

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]