@unique装饰器可以帮助我们检查保证没有重复值。

from enum import Enum, unique

@unique
class Weekday(Enum):   #定义一个星期的枚举类
    Sun = 0 # Sun的value被设定为0
    Mon = 1
    Tue = 2
    Wed = 3
    Thu = 4
    Fri = 5
    Sat = 6