proc PyIter_Check(obj: PyObject): bool {....raises: [], tags: [], forbids: [].}

proc PyIter_Next(iter: PyObject): PyObject {....raises: [], tags: [RootEffect],
    forbids: [].}

proc PyIter_NextItem(iter: PyObject; item: var PyObject): GetItemRes {.
    ...raises: [], tags: [RootEffect], forbids: [].}

template PyObject_GetIter(o: PyObject): PyObject