How would this feature be useful?

I normally run nox -s test to run my tests using the default Python version (the one nox is installed under, I guess?) This is my most common activity, and I'd like it to be straightforward. However, I sometimes want to run the tests for a specific Python version. I can do this by parametrising the Python version for the test session, but if I do that, nox -s test now means "run the test session for all Python versions.

Furthermore, I don't want to have to hard-code the list of Python versions. Doing that means I need to update the noxfile every time a new Python version comes out.

Describe the solution you'd like

If a session does not have the Python version parametrised, nox -s session --use-python 3.9 would run the given session with Python 3.9. Having -P as a short form for --use-python would be useful.

Describe alternatives you've considered

• Using @session(python=None, "3.8", "3.9", "3.10") looks like it might work, as it creates a session with no suffix. But that still runs all of the suffixed sessions, rather than just running the one session.
• --force-pythons sounds like it would work, but it doesn't, it just says "Python version selection caused no sessions to be selected".

Anything else?

No response