a = [('g', 10, 2), ('o', 6, 11), ('v', 2, 4), ('t', 1, 15), ('x', 40, 3), (
    'm', 4, 4), ('k', 10, 2), ('f', 14, 1), ('p', 70, 90), ('l', 21, 7), (
    'n', 1, 27), ('a', 39, 70), ('d', 11, 10), ('h', 21, 10), ('c', 10, 19),
    ('b', 8, 1), ('e', 30, 39), ('i', 23, 29), ('r', 8, 7), ('q', 2, 2), (
    's', 18, 86)]
Sorting a list of tuples by the addition of second and third element of the tuple