Python如何优雅的实现自增枚举类

class MyEnum:
    A = 'Apple'
    B = 'Banana'
    C = 'Cherry'

    @classmethod
    def list_values(cls):
        return [value for name, value in vars(cls).items() if not name.startswith('_')]

print(MyEnum.A)  # 输出：Apple
print(MyEnum.list_values())  # 输出：['Apple', 'Banana', 'Cherry']

class AutoNumberMeta(type):
    def __new__(cls, name, bases, dct):
        dct['_counter'] = 0
        return super().__new__(cls, name, bases, dct)

    def __init__(cls, name, bases, dct):
        for key, value in vars(cls).items():
            if value is None:
                setattr(cls, key, cls._counter)
                cls._counter += 1
        super().__init__(name, bases, dct)

class MyAutoEnum(metaclass=AutoNumberMeta):
    A = None
    B = None
    C = None

print(MyAutoEnum.A)  # 输出：0
print(MyAutoEnum.B)  # 输出：1
print(MyAutoEnum.C)  # 输出：2

from enum import Enum, auto

class MyEnum(Enum):
    A = auto()
    B = auto()
    C = auto()

print(MyEnum.A)  # 输出：MyEnum.A
print(MyEnum.B)  # 输出：MyEnum.B
print(MyEnum.C)  # 输出：MyEnum.C

class AutoIncrementEnum:
    _counter = 0

    def __init__(self):
        self.value = self._counter
        self._counter += 1

    def __repr__(self):
        return str(self.value)

class EnhancedEnum(AutoIncrementEnum):
    A = auto()
    B = auto()
    C = auto()

print(EnhancedEnum.A)  # 输出：0
print(EnhancedEnum.B)  # 输出：1
print(EnhancedEnum.C)  # 输出：2