In ArgParse, can two compatible formatter_class values be used?

[Gribouillis]

Looking into arpgarse's code, we see that ArgumentDefaultsHelpFormatter overrides a single method _get_help_string() and RawDescriptionHelpFormatter overrides only _fill_text(). It may depend on the python version, but I think you could try this

class MyFormatter(ArgumentDefaultsHelpFormatter, RawDescriptionHelpFormatter):
    pass

...formater_class=MyFormatter...