isOpen似乎是一个函数而不是属性吧
@typing.overload
def open(self, index: int, apiPreference: int, params: typing.Sequence[int]) -> bool: ...
def isOpened(self) -> bool: ...
def release(self) -> None: ...
def grab(self) -> bool: ...
@typing.overload
def retrieve(self, image: cv2.typing.MatLike | None = ..., flag: int = ...) -> tuple[bool, cv2.typing.MatLike]: ...
@typing.overload
这是opencv的源码