定义一个菜单

```python
菜单 = {
"1. 菜品一": "描述菜品一",
"2. 菜品二": "描述菜品二",
"3. 菜品三": "描述菜品三",
"4. 点餐完成": "感谢您的点餐，祝您用餐愉快！"
}

def show_menu():
for key, value in 菜单.items():
print(f"{key}. {value}")

show_menu()
```