       Callable[[EmailDeliveryInterface[_T]], EmailDeliveryInterface[_T]], None
        ] = None,
    ) -&gt; None:
        self.service = service
        self.override = override


class EmailDeliveryConfigWithService(ABC, Generic[_T]):
    def __init__(
        self,
        service: EmailDeliveryInterface[_T],
        override: Union[
            Callable[[EmailDeliveryInterface[_T]], EmailDeliveryInterface[_T]], None
        ] = None,
    ) -&gt; None:
        self.service = service
        self.overrid