[Python] How to define a immutable ClassVar in a python protocol?

I have an Enum and several classes using that Enum in an immutable class variable.

from typing import ClassVar, Protocol, Final, Literal
from enum import Enum

class MyEnum(Enum):
A = 0
B = 1

class MyClass1:
type: Final = MyEnum.A

class MyClass2:
type: Final = MyEnum.B


This works fine but I fail to define a protocol encompassing the two classes. Both:

class MyProtocol1(Protocol):
@property
def type(self) -> MyEnum: ...

class MyProtocol2(Protocol):
type: Final[MyEnum]


do not work for obvious reasons.

class MyProtocol3(Protocol):
@property
def type(self) -> ClassVar[MyEnum]: ...

class MyProtocol4(Protocol):
@property
@classmethod
def type(cls) -> MyEnum: ...


might achieve what I want but are not allowed. I thought about using a Generic with Literal, which also led nowhere. I am running out of ideas.

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