Argument Clinic: add support for deprecating keyword use of parameters

[erlend-aasland]

See #95065 (comment) by Serhiy. Quoting:

Turn positional-or-keyword parameters into positional-only parameters. A directive which means "the preceding positional-or-keyword parameters will be positional-only parameters in future".

In #95151, Argument Clinic learned how to deprecate positional use of parameters. In this issue, we propose to teach Argument Clinic how to deprecate keyword use of parameters.

Suggesting to use a similar syntax as the one introduced in #95151

func
   a: object
   / [from X.Y]

Meaning a will be positional-only from Python version X.Y. We can reuse parts of the code introduced in #95151 to implement this feature.

Linked PRs

• gh-107704: Argument Clinic: add support for deprecating keyword use of parameters #107984

[erlend-aasland]

cc. @serhiy-storchaka

[serhiy-storchaka]

I am working on this.

[erlend-aasland]

Thanks for doing this, Serhiy.