code: def add_subparsers(self, prog=None, **kwargs):
          
          if prog is None:
              # Use a non-shellish help formatter to avoid vt100 codes.
              f = argparse.HelpFormatter(prog=self.prog)
              f.add_usage(self.usage, self._get_positional_actions(),
                          self._mutually_exclusive_groups, '')
              prog = f.format_help().strip()
          return super().add_subparsers(prog=prog, **kwargs)
docs: Supplement a proper `prog` keyword argument for the subprocessor.
          The superclass technique for getting the `prog` value breaks because
          of our VT100 escape codes injected by `format_help`.