sum to zero (CodeEval) in python 3.x

main.py

# coding=utf-8
import sys
import itertools


def main():
    with open(sys.argv[1], 'r') as f:
        for line in f:
            digits = map(lambda e: int(e), line.rstrip().split(","))

            print(len([combination for combination
                       in itertools.combinations(digits, 4)
                       if sum(combination) == 0]))


if __name__ == "__main__":
    main()