Issue with 2.12 package when installed from source/PyPI: ipython=9.0 culprit

[valeriupredoi]

See issue when invoking the help option; I am not aware of any other options being broken apart from help but I need to investigate.

UPDATE:

• issue from ipython==9.0
• let know Fire in issue with brand new ipython==9.0 google/python-fire#587
• it appears it affects only the help option, and not run
• fix-pin for us in Pin ipython<9.0 #2681 - I don't think we ought to release a bugfix-release 2.12.1 - @bouweandela what say you?

[valeriupredoi]

issue isolated locally, and cause found: ipython=9.0 is causing it via fire. I'll open a PR to pin our ipython, and will let knoe fire about it 🔥

[valeriupredoi]

@sloosvel good news! The issue doesn't affect esmvaltool run so I think we don't need to bugfix-release 2.12.1 👍

[valeriupredoi]

OK the pin should still stay since Fire have solved the issue via google/python-fire#588 but they've not released a new build/version yet