[feature request] add support for positional-only and keyword-only arguments

[Clement-Lelievre]

Describe the request

Following this PEP and this one, Python allows
to force the way one passes arguments in functions or class methods, a.k.a keyword-only or positional-only arguments. (Requires Python >= 3.8)

It'd be nice to enhance the current code with the ability to parse * and / in the function's signature.

Thanks!