[BR]: ERROR: cannot import name 'MutableMapping' from 'collections' (/usr/lib/python3.11/collections/__init__.py) about fail2ban HOT 4 CLOSED

However, my version is higher than 1.0.2

No it is not, your version is 0.11.x that is obviously smaller than 1.0.x (0 < 1).
And there is indeed no 0.11.x version which could work with python >= 3.11.

You could try to install it from our releases provided here (no idea it'd be compatible with Ubuntu 20.04.6, but I don't see why not) - https://github.com/fail2ban/fail2ban/wiki/How-to-install-or-upgrade-fail2ban-manually#manual-installation-of-debian-upstream-package-released-here

from fail2ban.

Sorry, my fault. I saw 0.11.1-1 as 1.11.1-1 by mistake.

from fail2ban.

After changing apt source and reinstall fail2ban, it works for me though its version is 0.11.2

root@Ali-BJ:~# fail2ban-client version
0.11.2
root@Ali-BJ:~#

from fail2ban.

it works for me though its version is 0.11.2

Then it either uses different python version (see fail2ban-python --version) or it was patched by the maintainers of that repo.

from fail2ban.