def __next__(self):
        try:
            if not self._origin_iter:
                self._origin_iter = self._origin.__iter__()
            n = next(self._origin_iter)
        except __HOLE__ as e:
            self._finished = True
            raise e
        else:
            self._state.append(n)
            return n
dataset/ETHPy150Open graphql-python/graphene/graphene/utils/lazylist.py/LazyList.__next__