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对象比较装饰器——@total_ordering

@total_ordering 是 Python 中一个有趣的功能，它可以自动生成对象比较的其他运算符，只需要实现其中一个比较方法即可。这个装饰器可以方便地实现对象的比较，但也有一些性能和复杂性的权衡。

因为创建类实例对象的内存地址不一样，通常无法使用 == 运算符进项比较。

示例代码
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from functools import total_ordering
from typing import Self

class Person:
    def __init__(self, name: str, age: int) -> None:
        self.name = name
        self.age = age

    def work(self) -> None:
        print(f'{self.name} is working...')

    def eat(self) -> None:
        print(f'{self.name} cannot eat right now, because they have to work...')

    def sleep(self) -> None:
        print(f'{self.name} is now sleeping, but dreams about working...')

def main() -> None:
    bob: Person = Person('Bob',35)
    luigi: Person = Person('Luigi', 40)
    bob2: Person = Person('Bob', 35)
    print(bob == luigi)  # False
    print(bob == bob2)  # False

1. 使用内置构造方法

使用 __eq__、__ne__、__lt__、__gt__、__le__、__ge__ 等构造方法可实现两个对象的大小比较，比较麻烦的是，要实现两个对象的完整比较操作，需要将这些方法都实现一遍。

使用内置构造方法
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class Person:
    def __init__(self, name: str, age: int) -> None:
        self.name = name
        self.age = age

    def work(self) -> None:
        print(f'{self.name} is working...')

    def eat(self) -> None:
        print(f'{self.name} cannot eat right now, because they have to work...')

    def sleep(self) -> None:
        print(f'{self.name} is now sleeping, but dreams about working...')

    def __eq__(self, other: Self) -> bool:
        return self.__dict__ == other.__dict__

    def __ne__(self, other: Self) -> bool:
        return not self.__eq__(other)

    def __lt__(self, other: Self) -> bool:
        return (self.name.lower(), self.age) < (other.name.lower(), other.age)

    def __gt__(self, other: Self) -> bool:
        return not self.__lt__(other) and self != other

    def __le__(self, other: Self) -> bool:
        return self.__lt__(other) or self.__eq__(other)

    def __ge__(self, other: Self) -> bool:
        return self.__gt__(other) or self.__eq__(other)

2. 使用装饰器--@total_ordering

@total_ordering 是一个装饰器，它可以自动生成对象比较的其他运算符，只需要实现其中一个比较方法即可，例如你想实现 A < B 和 B >= A，那么只需要实现 A < B 就可以了，即实现 __lt__。

@total_ordering
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@total_ordering
class Person:
    def __init__(self, name: str, age: int) -> None:
        self.name = name
        self.age = age

    def work(self) -> None:
        print(f'{self.name} is working...')

    def eat(self) -> None:
        print(f'{self.name} cannot eat right now, because they have to work...')

    def sleep(self) -> None:
        print(f'{self.name} is now sleeping, but dreams about working...')

    def __eq__(self, other: Self) -> bool:
        return self.__dict__ == other.__dict__

    def __lt__(self, other: Self) -> bool:
        return (self.name.lower(), self.age) < (other.name.lower(), other.age)