[('b', 9), ('d', 9), ('a', 10), ('c', 10)] или
[('b', 9), ('d', 9), ('с', 10), ('a', 10)] или
[('d', 9), ('b', 9), ('a', 10), ('c', 10)] и т.д.

>>> import random
>>> sorted([1,2,3], key=lambda _: random.randrange(10))
[2, 1, 3]
>>> sorted([1,2,3], key=lambda _: random.randrange(10))
[1, 3, 2]