使用mypy时Python继承与多态类型检查报错的解决方法

我希望在mypy中实现标准的多态特性，但此前从未使用过mypy，操作起来并不直观。

基类代码 #

class ContentPullOptions:
    pass


class Tool(Protocol):
    async def pull_content(self, opts: ContentPullOptions) -> str | Dict[str, Any]: ...

子类代码 #

class GoogleSearchOptions(ContentPullOptions):
    query: str
    sites: List[str]


class GoogleSearchTool(Tool):
    async def pull_content(
        self,
        opts: GoogleSearchOptions,
    ) -> str | Dict[str, Any]:

运行mypy时报错 #

error: Argument 1 of "pull_content" is incompatible with supertype "Tool"; supertype defines the argument type as "ContentPullOptions"

请问在mypy中进行此类基础继承类型检查，最易维护且简洁的实现方式是什么？我尝试过自定义类型、类型转换等方法，但都显得繁琐且不清晰。

解决方案 #

（该方案可能仍违反里氏替换原则）

from typing import TypeVar, Protocol, Dict, Any, List, Callable

# 定义逆变类型变量T_contra
T_contra = TypeVar('T_contra', bound=ContentPullOptions, contravariant=True)

class ContentPullOptions:
    pass

class Tool(Protocol[T_contra]):
    async def pull_content(self, opts: T_contra) -> str | Dict[str, Any]: ...

class GoogleSearchOptions(ContentPullOptions):
    query: str
    sites: List[str]

class GoogleSearchTool:
    async def pull_content(
        self,
        opts: GoogleSearchOptions,
    ) -> str | Dict[str, Any]:
        # 实现逻辑
        pass

内容的提问来源于stack exchange，提问作者Ryan