LinuxQuestions.org - borked python upgrade

TL;DR - installed a newer version of python3. It fixed several things but broke several other things. How to make it all work?

Full version: ubuntu 18.04 - officially still supported, but canonical is doing a crappy job and python3 got so old than some programs started complaining. Installed the latest version 3.10 from https://launchpad.net/~deadsnakes/+archive/ubuntu/ppa beside the existing 3.6 from the official repo and changed the /usr/bin/python3 link to point to /usr/bin/python3.10. Programs which were requiring something newer were satisfied, but it broke several things:

unknown command handling from bash no longer works

Code:

Traceback (most recent call last):

  File "/usr/lib/command-not-found", line 28, in <module>

    from CommandNotFound import CommandNotFound

  File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 19, in <module>

    from CommandNotFound.db.db import SqliteDatabase

  File "/usr/lib/python3/dist-packages/CommandNotFound/db/db.py", line 5, in <module>

    import apt_pkg

ModuleNotFoundError: No module named 'apt_pkg'

as well as some package handling stuff from cron

Code:

Aug 30 06:01:48 server apt.systemd.daily[2813]: Traceback (most recent call last):

Aug 30 06:01:48 server apt.systemd.daily[2813]:  File "/usr/bin/unattended-upgrade", line 32, in <module>

Aug 30 06:01:48 server apt.systemd.daily[2813]:    from gi.repository.Gio import NetworkMonitor

Aug 30 06:01:48 server apt.systemd.daily[2813]:  File "/usr/lib/python3/dist-packages/gi/__init__.py", line 42, in <module>

Aug 30 06:01:48 server apt.systemd.daily[2813]:    from . import _gi

Aug 30 06:01:48 server apt.systemd.daily[2813]: ImportError: cannot import name '_gi' from partially initialized module 'gi' (most likely due to a circular import) (/usr/lib/python3/dist-packages/gi/__init__.py)



Aug 29 19:35:07 server dbus-daemon[1050]: [session uid=1000 pid=1048] Activating service name='org.kubuntu.DriverManager' requested by ':1.5' (uid=1000 pid=1422 comm="kded5 [kdeinit5]                                  " label="unconfined")

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]: Traceback (most recent call last):

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:  File "/usr/lib/x86_64-linux-gnu/libexec/DriverManager_DBus", line 24, in <module>

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:    import dbus

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:  File "/usr/lib/python3/dist-packages/dbus/__init__.py", line 77, in <module>

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:    import dbus.types as types

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:  File "/usr/lib/python3/dist-packages/dbus/types.py", line 6, in <module>

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]:    from _dbus_bindings import (

Aug 29 19:35:07 server org.kubuntu.DriverManager[1050]: ModuleNotFoundError: No module named '_dbus_bindings'

Aug 29 19:35:07 server dbus-daemon[1050]: [session uid=1000 pid=1048] Activated service 'org.kubuntu.DriverManager' failed: Process org.kubuntu.DriverManager exited with status 1





Aug 29 19:35:07 server org.debian.AptXapianIndex[847]: Traceback (most recent call last):

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:  File "/usr/sbin/update-apt-xapian-index", line 66, in <module>

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:    import axi.indexer

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:  File "/usr/lib/python3/dist-packages/axi/indexer.py", line 31, in <module>

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:    import xapian

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:  File "/usr/lib/python3/dist-packages/xapian/__init__.py", line 24, in <module>

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]:    from . import _xapian

Aug 29 19:35:07 server org.debian.AptXapianIndex[847]: ImportError: cannot import name '_xapian' from partially initialized module 'xapian' (most likely due to a circular import) (/usr/lib/python3/dist-packages/xapian/__init__.py)

I am not a python guru and in a bit of a loss - how can I transfer/install/index/convert/make available/whatever the stuff which works in 3.6 to 3.10? Note that all these errors are about the stuff installed in a shared /usr/lib/python3/dist-packages directory, not a version-specific site-packages. Or should I abandon the idea, create a separate environment for finicky programs and leave 3.6 as the default?