#!/usr/bin/env python3


import concurrent.futures


def add(x):
    s = 0
    for e in x:
        s += e
    return s


#with concurrent.futures.ProcessPoolExecutor() as e:
with concurrent.futures.ThreadPoolExecutor() as e:
    print(tuple(e.map(add, [[1, 2, 3], [1, 2], [3, 4]])))