from abc import abstractmethod
from dataclasses import dataclass

class QuasiABC:
    @property
    @abstractmethod
    def x(self) -> int: ...

    @x.setter
    #@abstractmethod
    def x(self, val) -> int: ...
    
@dataclass(frozen=True)
class E(QuasiABC):
    x: int

print(E(10))