class CustomHelpFormatter(argparse.HelpFormatter):

    def _format_action_invocation(self, action):
        if not action.option_strings or action.nargs == 0:
            return super()._format_action_invocation(action)
default = self._get_default_metavar_for_optional(action)
args_string = self._format_args(action, default)
return ', '.join(action.option_strings) + ' ' + args_string
fmt = lambda prog: CustomHelpFormatter(prog)
parser = argparse.ArgumentParser(formatter_class=fmt)
Не показывать длинные опции дважды в print_help() из argparse