itertools - Functions creating iterators for efficient looping

The itertools library makes it easy to generate Perumatation from both strings and list. The code example below show all perumataiton of number pairs. 1. number pairs import itertools x = [1, 2, 3, 4, 5, 6] # output all permutations of x print(list(itertools.permutations(x, 2))) # output [(1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 3), (2, 4), (2, 5), (2, 6), (3, 1), (3, 2), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 5), (4, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5)] 2.