gh-95065, gh-107704: Argument Clinic: support multiple '/ [from ...]' and '* [from ...]' markers

[serhiy-storchaka]

It does not even make the code much more complex. Simply the code which checks that the version is the same is replaced with the code which supports multiple versions.

$ git diff main... --stat Tools/clinic/clinic.py
Tools/clinic/clinic.py | 105 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------------------------------------------
1 file changed, 55 insertions(+), 50 deletions(-)

• Issue: Argument Clinic: add support for deprecating positional use of parameters #95065

• Issue: Argument Clinic: add support for deprecating keyword use of parameters #107704

[erlend-aasland]

It does not even make the code much more complex. Simply the code which checks that the version is the same is replaced with the code which supports multiple versions.

Indeed, the refactors from your previous PR came in handy here.

[erlend-aasland]

Thanks, this is nice; @AlexWaygood, are you fine with this feature?

[AlexWaygood]

This looks pretty good to me! I'm impressed how little extra code it takes. I have one readability style nit.

I think we should maybe also add one or two examples to https://docs.python.org/3.13/howto/clinic.html#how-to-deprecate-passing-parameters-positionally-or-by-keyword that have mutliple / [from ...] and * [from ...] markers