User
. . . >>> sorted(l, cmp=lambda x, y: 0 if sign(x) == sign(y) else cmp(x, y)) [-10, -9, -5, -1, -7, -3, -4, -8, -6, -2, 0, 7, 8, 3, 4, 6, 2, 9, 5, 1]
