docs: def _get_subparsers(self, dest):
          """Get named subparsers."""
          if not self._subparsers:
              self._subparsers = self.parser.add_subparsers(dest=dest)
          elif self._subparsers.dest != dest:
              raise KeyError(
                  "Subparser names mismatch. You can only create one subcommand.")
          return self._subparsers