Argparse: add method for retrieving the parsers of actions

Feature or enhancement

Proposal:

I have a CLI interface with an argparse.ArgumentParser composed of a bunch of different actions. I was trying to validate if an argument had been set to a default value, and with just the main parser available, I was having some issues using get_default() working from the main parser, rather than the parsers for the various actions.

I ended up going with the following comparison, in order to reduce the amount of refactoring I would need to do, where args is the var holding the object returned from parse_args():

        args.my_param == parser._actions[1].choices[args.action]].get_default(args.my_param)

I could also have solved this by adding a wrapper class holding all the subparsers in an object of some kind.

But - I think it would be nice to have a public method for accessing these action parsers, mostly for enabling this kind of use case.

Has this already been discussed elsewhere?

Not that I could find

Links to previous discussion of this feature:

No response

Beginne mit argparse.ArgumentParser, der Sammlung _actions des Parsers, den subparser choices und get_default(). Ermittle den vorgesehenen Umfang und das Verhalten der öffentlichen Methode zum Abrufen von Action-Parsern, einschließlich der Frage, wie sie den beschriebenen Anwendungsfall zur Validierung von Standardwerten unterstützen soll. Als abgeschlossen gilt die Aufgabe, wenn die API und ihr Verhalten klar definiert sind und das Feature durch geeignete Tests abgedeckt ist.