Given the following definition:

class MyEnum(IntEnum):
    a = 1
    b = 2
    c = 3
    d = 4

I am looking for an expression which replaces SomeExpression which will both statically assert that the value myEnum is either MyEnum.c | MyEnum.d in that branch – such that the ‘never’ case at the bottom correctly infers type never – and will, of course, ensure at runtime that the correct branch is taken such that ‘matched’ is output to the console.

def check(myEnum: MyEnum):
    match myEnum:
        case SomeExpression:
            print("matched")
        case MyEnum.a:
            pass
        case MyEnum.b:
            pass
        case never:
            assert_never(never)

Is there any such way to achieve this in python? I’ve tried using simpler methods like a predicate inside the match which does not narrow the type statically as desired. I’ve also investigated __class_getitem__ but not been able to get it working as expected.