__contains__ is not reconize as a None check

I am struggling a bit on making mypy validate the type of an Iterable containing Optional:

def func_1(address: Address) -> Optional[float] :
    ...

def func_2(addresses: Tuple[Addresses, ...]) -> Optional[Tuple[float, ...]]:
    ordered_tuple = tuple(
        func_1(address)
        for address in addresses)
    return ordered_tuple if not None in ordered_tuple else None

Mypy seems to do not recognize the check if not None in ordered_tuple else None.
A workaround that I found is to check all the values returned by func_1 :

def func_1(address: Address) -> Optional[float] :
    ...

def func_2(addresses: Tuple[Addresses, ...]) -> Optional[Tuple[float, ...]]:
    ordered_list = []
    for address in addresses:
        value = func_1(address)
        if value is not None:
            ordered_list.append(value)
        else:
            return None
    return tuple(ordered_list)

issue にはファイルもテストも指定されていません。まず mypy で 2 つの例を再現し、None in ordered_tuple に対する型チェックの動作を調べてください。最初のバージョンが、意図した Optional から non-Optional なタプルへの絞り込みを伴って受け入れられ、既存の workaround も引き続き有効であれば完了です。