Comment 12 for bug 1979663

I went through the verification process for this bug, and it does successfully solves the issue.

Here it's the terminal log and screenshots that serve as evidence.

$ juju export-bundle | pastebinit
https://paste.ubuntu.com/p/tF3XF2Sp9Y/
$ juju ssh openstack-dashboard/0
Welcome to Ubuntu 20.04.5 LTS (GNU/Linux 5.4.0-132-generic x86_64)
...
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ apt policy python3-magnumclient
python3-magnumclient:
  Installed: 2.11.0-0ubuntu4
  Candidate: 2.11.0-0ubuntu4
  Version table:
 *** 2.11.0-0ubuntu4 500
        500 http://nova.clouds.archive.ubuntu.com/ubuntu focal/main amd64 Packages
        100 /var/lib/dpkg/status
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ sudo vim /etc/apt/sources.list # enabling -proposed
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ sudo apt-get update -qqq
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ apt policy python3-magnumclient
python3-magnumclient:
  Installed: 2.11.0-0ubuntu4
  Candidate: 2.11.0-0ubuntu6
  Version table:
     2.11.0-0ubuntu6 500
        500 http://nova.clouds.archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages
 *** 2.11.0-0ubuntu4 500
        500 http://nova.clouds.archive.ubuntu.com/ubuntu focal/main amd64 Packages
        100 /var/lib/dpkg/status
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ sudo apt install --only-upgrade python3-magnumclient
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
  python-magnumclient-doc
The following packages will be upgraded:
  python3-magnumclient
1 upgraded, 0 newly installed, 0 to remove and 37 not upgraded.
Need to get 68.0 kB of archives.
After this operation, 1024 B disk space will be freed.
Get:1 http://nova.clouds.archive.ubuntu.com/ubuntu focal-proposed/main amd64 python3-magnumclient all 2.11.0-0ubuntu6 [68.0 kB]
Fetched 68.0 kB in 0s (870 kB/s)
(Reading database ... 90151 files and directories currently installed.)
Preparing to unpack .../python3-magnumclient_2.11.0-0ubuntu6_all.deb ...
Unpacking python3-magnumclient (2.11.0-0ubuntu6) over (2.11.0-0ubuntu4) ...
Setting up python3-magnumclient (2.11.0-0ubuntu6) ...
/usr/lib/python3/dist-packages/magnumclient/tests/utils.py:98: SyntaxWarning: "is" with a literal. Did you mean "=="?
  if key is 'location':
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ sudo systemctl restart apache2
ubuntu@juju-0b0ca0-zaza-25be274c0f2c-18:~$ apt policy python3-magnumclient
python3-magnumclient:
  Installed: 2.11.0-0ubuntu6
  Candidate: 2.11.0-0ubuntu6
  Version table:
 *** 2.11.0-0ubuntu6 500
        500 http://nova.clouds.archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     2.11.0-0ubuntu4 500
        500 http://nova.clouds.archive.ubuntu.com/ubuntu focal/main amd64 Packages