def greet(name: str, lang: str = "en") -> str:
    if lang == "zh":
        return f"你好,{name}!"
    if lang == "es":
        return f"¡Hola, {name}!"
    return f"Hello, {name}!"


if __name__ == "__main__":
    print(greet("world"))
    print(greet("世界", lang="zh"))
    print(greet("mundo", lang="es"))