This is vendored from Starlette to avoid importing private symbols.
    """

    def __init__(self, cm: AbstractContextManager[_T]) -> None:
        self._cm = cm

    async def __aenter__(self) -> _T:
        return self._cm.__enter__()

    async def __aexit__(
        self,
        exc_type: type[BaseException] | None,
        exc_value: BaseException | None,
        traceback: types.TracebackType | None,