Source: 📖 Effective Python item 36

itertools.accumulate

This function can return running totals:

values = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
running_totals = itertools.accumulate(values)

print(list(running_totals))

>>>
[1, 3, 6, 10, 15, 21, 28, 36, 45, 55]