cstutoringcenter.com_Reverse of a reverse

sum = 0
for file in open("p94.txt", "r"):
    l = file.replace("\n", "").split(" ")
    l[0] = list(l[0])
    l[1] = list(l[1])
    l[0].reverse()
    l[1].reverse()
    sum += int(''.join(list(str(int(''.join(l[0])) + int(''.join(l[1]))))))
print ''.join(list(str(sum))[::-1])