Discrepancy between python3-defaults (and the `python3` symlink) and the actual version of Python installed by python3.8

[Thomas Ward]

Per the SRU done at https://launchpad.net/bugs/1889218 to update Focal's Python via SRU to 3.8.5, there is a leftover discrepancy on python3-defaults (and the corresponding `python3` package itself, NOT the `python3.8` binaries pulled in by it) as to which version is in place.

The `python3-defaults` and `python3` for Focal is listed as 3.8.2 in rmadison:

 python3-defaults | 3.8.2-0ubuntu2 | focal | source
 python3 | 3.8.2-0ubuntu2 | focal | amd64, arm64, armhf, i386, ppc64el, riscv64, s390x

However, per the SRU, Python 3.8 was updated to Python 3.8.5 in both -updates and -security:

 python3.8 | 3.8.2-1ubuntu1 | focal | source, amd64, arm64, armhf, i386, ppc64el, riscv64, s390x
 python3.8 | 3.8.5-1~20.04 | focal-security | source, amd64, arm64, armhf, i386, ppc64el, riscv64, s390x
 python3.8 | 3.8.5-1~20.04 | focal-updates | source, amd64, arm64, armhf, i386, ppc64el, riscv64, s390x

Unfortunately, this leaves a version discrepancy between python3.8's version of 3.8.5 and the corresponding version entry on -defaults.

This may be able to be resolved by respinning -defaults and putting it in both -security and -updates as a post-SRU-fix to fix the discrepancy.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Chris Guiver (guiverc)]

I just made a comment on askubuntu where I relied on a `rmadison python3` query which indicated to me 3.8.2 was the default python3 for an updated focal system.. and the user responded 3.8.5 which isn't the answer I expected.

This impacts me too.

[Julian Andres Klode (juliank)]

The correct way to check for the python version is to figure out the major version (here 3.8) by looking at python3, and then looking at python<major>, here python3.8.

The versions are not matching in other releases either, e.g. bionic has defaults 3.6.5/3.6.7, but python3.6 is at 3.6.5/3.6.9. xenial has 3.5.1 default, 3.5.2 python3.5.

This is normal and expected; changing it would not do anything useful, just trigger a ton of autopkgtests.