The same changes to the python is python2 quirk exist in the Impish version of ubuntu-release-upgrader although the quirk has been disabled as it is unnecessary.
https://launchpadlibrarian.net/546274717/ubuntu-release- upgrader_1%3A21.10.3_1%3A21.10.4.diff.gz ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Fix Released ** Description changed: [Impact] Users with universe not enabled and python2 packages installed are unable to upgrade from Ubuntu 18.04 to Ubuntu 20.04. - [Test Case] + [Test Plan] ----------- On an Ubuntu 18.04 system with universe and multiverse disabled 1) apt-get install duplicity (it depends on python2.7) 2) run do-release-upgrade Observe the upgrader hang at Calculating the changes (in text mode) kill it and observe a Traceback in /var/log/dist-upgrade/main.log. ... - File "/usr/lib/python3/dist-packages/apt/cache.py", line 303, in __getitem__ - raise KeyError('The cache has no package named %r' % key) + File "/usr/lib/python3/dist-packages/apt/cache.py", line 303, in __getitem__ + raise KeyError('The cache has no package named %r' % key) KeyError: "The cache has no package named 'python-is-python2'" With the version of the release-upgrader from -proposed (do-release- upgrade -p) you'll instead receive a message regarding universe not being enabled and the need to either remove python2 packages or enable universe. [Original Description] This is because python-minimal was installed and universe was not enabled on the system being upgraded. Error Tracker buckets: https://errors.ubuntu.com/problem/f92900f3c057db7600d88857e7c05434b69d2496 https://errors.ubuntu.com/problem/23e6edb38993cb74331d30beeadccdfffe1d557a ProblemType: CrashDistroRelease: Ubuntu 20.04 Package: ubuntu-release-upgrader-core 1:20.04.31 ProcVersionSignature: Ubuntu 5.4.0-71.79~18.04.1-generic 5.4.101 Uname: Linux 5.4.0-71-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.23 Architecture: amd64 CrashDB: ubuntu Date: Thu Apr 15 10:59:53 2021 ExecutablePath: /usr/bin/do-release-upgrade ExecutableTimestamp: 1606763386 InstallationDate: Installed on 2021-04-13 (1 days ago) InstallationMedia: Ubuntu 18.04.5 LTS "Bionic Beaver" - Release amd64 (20200806.1) InterpreterPath: /usr/bin/python3.6 PackageArchitecture: all ProcCmdline: /usr/bin/python3 -s ./focal --frontend DistUpgradeViewText ProcCwd: /tmp/ubuntu-release-upgrader-e397n4sn ProcEnviron: TERM=screen SHELL=/bin/bash LANG=en_US.UTF-8 LC_CTYPE=en_US.UTF-8 PATH=(custom, no user) Python3Details: /usr/bin/python3.6, Python 3.6.9, python3-minimal, 3.6.7-1~18.04 PythonArgs: ['/usr/bin/do-release-upgrade', '--frontend', 'DistUpgradeViewText'] PythonDetails: /usr/bin/python2.7, Python 2.7.17, python-minimal, 2.7.15~rc1-1SourcePackage: ubuntu-release-upgrader Title: do-release-upgrade crashed with KeyError in __getitem__(): "The cache has no package named 'python-is-python2'" UpgradeStatus: Upgraded to bionic on 2021-04-15 (0 days ago) ** Description changed: [Impact] Users with universe not enabled and python2 packages installed are unable to upgrade from Ubuntu 18.04 to Ubuntu 20.04. [Test Plan] ----------- On an Ubuntu 18.04 system with universe and multiverse disabled 1) apt-get install duplicity (it depends on python2.7) 2) run do-release-upgrade Observe the upgrader hang at Calculating the changes (in text mode) kill it and observe a Traceback in /var/log/dist-upgrade/main.log. ... File "/usr/lib/python3/dist-packages/apt/cache.py", line 303, in __getitem__ raise KeyError('The cache has no package named %r' % key) KeyError: "The cache has no package named 'python-is-python2'" With the version of the release-upgrader from -proposed (do-release- upgrade -p) you'll instead receive a message regarding universe not being enabled and the need to either remove python2 packages or enable universe. + + [Where problems could occur] + The switch to using the finally clause in DistUpgradeCache.py is a significant (albeit safe) change but it is necessary for the error message to actually be displayed. So it'd make sense to run through a whole release upgrade to ensure that the gui behaves normally. [Original Description] This is because python-minimal was installed and universe was not enabled on the system being upgraded. Error Tracker buckets: https://errors.ubuntu.com/problem/f92900f3c057db7600d88857e7c05434b69d2496 https://errors.ubuntu.com/problem/23e6edb38993cb74331d30beeadccdfffe1d557a ProblemType: CrashDistroRelease: Ubuntu 20.04 Package: ubuntu-release-upgrader-core 1:20.04.31 ProcVersionSignature: Ubuntu 5.4.0-71.79~18.04.1-generic 5.4.101 Uname: Linux 5.4.0-71-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.23 Architecture: amd64 CrashDB: ubuntu Date: Thu Apr 15 10:59:53 2021 ExecutablePath: /usr/bin/do-release-upgrade ExecutableTimestamp: 1606763386 InstallationDate: Installed on 2021-04-13 (1 days ago) InstallationMedia: Ubuntu 18.04.5 LTS "Bionic Beaver" - Release amd64 (20200806.1) InterpreterPath: /usr/bin/python3.6 PackageArchitecture: all ProcCmdline: /usr/bin/python3 -s ./focal --frontend DistUpgradeViewText ProcCwd: /tmp/ubuntu-release-upgrader-e397n4sn ProcEnviron: TERM=screen SHELL=/bin/bash LANG=en_US.UTF-8 LC_CTYPE=en_US.UTF-8 PATH=(custom, no user) Python3Details: /usr/bin/python3.6, Python 3.6.9, python3-minimal, 3.6.7-1~18.04 PythonArgs: ['/usr/bin/do-release-upgrade', '--frontend', 'DistUpgradeViewText'] PythonDetails: /usr/bin/python2.7, Python 2.7.17, python-minimal, 2.7.15~rc1-1SourcePackage: ubuntu-release-upgrader Title: do-release-upgrade crashed with KeyError in __getitem__(): "The cache has no package named 'python-is-python2'" UpgradeStatus: Upgraded to bionic on 2021-04-15 (0 days ago) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1924604 Title: do-release-upgrade crashed with KeyError in __getitem__(): "The cache has no package named 'python-is-python2'" To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1924604/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
