def METHOD_NAME(self, lang, command):
    code = textwrap.dedent(f"""\
        letters is a, b, b
        {command} letters""")
    self.multi_level_tester(
        lang=lang,
        code=code,
        max_level=11,
        exception=hedy.exceptions.InvalidArgumentTypeException,
        extra_check_function=self.exception_command(command)
    )