Comment 3 for bug 2038949

That's actually not what's causing the upgrade to fail. While there is something wrong with "c..archive.ubuntu.com", the upgrader will just just "arhive.ubuntu.com instead. E.g., from VarLogDistupgradeMainlog.txt:

2023-10-10 16:20:29,075 DEBUG upgrade from old-releases.ubuntu.com detected
2023-10-10 16:20:29,075 DEBUG verifySourcesListEntry: deb http://c..archive.ubuntu.com/ubuntu lunar main restricted
2023-10-10 16:20:29,075 DEBUG url_downloadable: http://c..archive.ubuntu.com/ubuntu/dists/lunar/Release
2023-10-10 16:20:29,075 DEBUG s='http' n='c..archive.ubuntu.com' p='/ubuntu/dists/lunar/Release' q='' f=''
2023-10-10 16:20:29,080 DEBUG error from httplib: 'encoding with 'idna' codec failed (UnicodeError: label empty or too long)'
2023-10-10 16:20:29,080 DEBUG verifySourcesListEntry: deb http://archive.ubuntu.com/ubuntu lunar main restricted
2023-10-10 16:20:29,080 DEBUG url_downloadable: http://archive.ubuntu.com/ubuntu/dists/lunar/Release
2023-10-10 16:20:29,080 DEBUG s='http' n='archive.ubuntu.com' p='/ubuntu/dists/lunar/Release' q='' f=''
2023-10-10 16:20:29,096 INFO transition from old-release.u.c to http://archive.ubuntu.com/ubuntu

The real error, seen in VarLogDistupgradeAptlog.txt, is this:

  MarkInstall python3.10-venv:amd64 < 3.10.7-1ubuntu0.4 @ii mK Ib > FU=0
    python3.10-venv:amd64 Depends on python3.10-distutils:amd64 < none @un mH > can't be satisfied! (dep)
  MarkInstall xfsprogs:amd64 < 5.16.0-1ubuntu1 -> 6.1.0-1ubuntu1 @ii umU Ib > FU=0
  Installing libicu72:amd64 as Depends of xfsprogs:amd64
    MarkInstall libicu72:amd64 < none -> 72.1-3ubuntu2 @un uN > FU=0
   Upgrading: libgs9:amd64 < 9.56.1~dfsg1-0ubuntu3.2 @ii mK Ib > due to libgs9:amd64 Depends on libgs9-common:amd64 < 9.56.1~dfsg1-0ubuntu3.2 -> 10.0.0~dfsg1-0ubuntu1.3 @ii umU Ib > (= 9.56.1~dfsg1-0ubuntu3.2)
  MarkInstall libgs9-common:amd64 < 9.56.1~dfsg1-0ubuntu3.2 -> 10.0.0~dfsg1-0ubuntu1.3 @ii umU Ib > FU=0
    MarkInstall libgs9:amd64 < 9.56.1~dfsg1-0ubuntu3.2 @ii mK Ib > FU=0
      libgs9:amd64 Depends on libgs9-common:amd64 < 9.56.1~dfsg1-0ubuntu3.2 -> 10.0.0~dfsg1-0ubuntu1.3 @ii pumU Ib > (= 9.56.1~dfsg1-0ubuntu3.2) can't be satisfied! (dep)

Normally these sort of things with python are caused by using the python deadsnakes PPA. I am not sure about the other package at the moment, though.