Can you please post the contents of /etc/apt/sources.list?

@ArchismanPanigrahi Sure

The source of the problem is libpython3.10 : Depends: libpython3.10-stdlib (= 3.10.12-1~22.04.3) but 3.10.14-1+focal1 is to be installed. Somehow the focal version has higher version number than the jammy version, and there must be a focal repository somewhere inside /etc/apt/. Are any PPAs activated, e.g. the deadsnakes PPA?

@ArchismanPanigrahi When I run software-properties-gtk, every single source in the "Other software" tab is unchecked. I'm not sure if I can trust this front-end, though. Is there a config file I can check to be sure?

Please post the output of apt cache policy libpython3.10-stdlib

Silly question - did you run sudo apt update before trying to install gnome-control-center?

The GTK frontend shows all the PPAs, but it cannot always show error with misconfigured official repositories.

@ArchismanPanigrahi Did you mean apt-cache policy? I updated the post. I've been running apt update at various times all day in between attempts, so yeah

Try sudo apt install libpython3.10-stdlib=3.10.12-1~22.04.3 (before confirming the installation, ensure that it does not remove all python packages or many important system packages, if that happens, don't proceed)

I get a slightly different error - libpython3.10-stdlib : Depends: libpython3.10-minimal (= 3.10.12-1~22.04.3) but 3.10.14-1+focal1 is to be installed

If I try

then I get

Hmm, it seems that the python installation is messed up. One can try downloading .deb packages for python from packages.ubuntu.com and installing manually using dpkg, but that may break the desktop environment if things go wrong. If you don't want to take that risk, I would suggest fresh installing 24.04. However, you can wait a few days before doing that and look out for other solutions.

okay, thanks

I will keep documenting the problem here

is there a way to "remove" entries from apt-cache policy?

I can see that the focal version is higher priority than the jammy ones for python3.10

I really don't know.

Focal version is not supposed to have a higher version number than the jammy version. I don't know how this focal version got installed, because this package seems to be absent in official repositories.