Abstract class trong Python — dùng thế nào?

from abc import ABC, abstractmethod

class Repository(ABC):
    @abstractmethod
    async def get_by_id(self, id: int): ...

    @abstractmethod
    async def create(self, data: dict): ...

    def find_all(self):          # Concrete method — có thể kế thừa
        return self.get_all()

class UserRepository(Repository):
    async def get_by_id(self, id): ...   # Bắt buộc implement
    async def create(self, data): ...    # Bắt buộc implement

# Repository()  # TypeError — cannot instantiate abstract class