def question_mark(self):
        """Shows help for this command and it's sub-commands.
        """
        ret = []
        if self.param_help_msg or len(self.subcommands) == 0:
            ret.append(self._quick_help())

        if len(self.subcommands) > 0:
            for k, _ in sorted(self.subcommands.items()):
                command_path, param_help, cmd_help = \
                    self._instantiate_subcommand(k)._quick_help(nested=True)
                if command_path or param_help or cmd_help:
                    ret.append((command_path, param_help, cmd_help))

        return (
            CommandsResponse(STATUS_OK, self.help_formatter(ret)),
            self.__class__
        )
Shows help for this command and it's sub-commands.