code: def extra(self, argument_dest, **kwargs):
          
          self._check_stale()
          if not self._applicable():
              return
  
          if self.command_scope in self.command_loader.command_group_table:
              raise ValueError("command authoring error: extra argument '{}' cannot be registered to a group-level "
                               "scope '{}'. It must be registered to a specific command.".format(
                                   argument_dest, self.command_scope))
  
          deprecate_action = self._handle_deprecations(argument_dest, **kwargs)
          if deprecate_action:
              kwargs['action'] = deprecate_action
          self.command_loader.extra_argument_registry[self.command_scope][argument_dest] = CLICommandArgument(
              argument_dest, **kwargs)
docs: Register extra parameters for the given command. Typically used to augment auto-command built
          commands to add more parameters than the specific SDK method introspected.
  
          :param argument_dest: The destination argument to add this argument type to
          :type argument_dest: str
          :param kwargs: Possible values: `options_list`, `validator`, `completer`, `nargs`, `action`, `const`, `default`,
                         `type`, `choices`, `required`, `help`, `metavar`. See /docs/arguments.md.