In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['l', 7331, 'b', 7563, 'K', 8139, 7019, 'g', 9743, 5063, 4213, 2721, 6971, 'F', 'a', 4455, 6945, '8421', '5767', 'P', 'y', 'k', 'U', '4099', '1639', 'M', '2415', '7821', '9365', 'O', 'r', '5485', 'J', '2813', 'k', '7481', '5221', '9233', 'O', 'B', 'M'], [4435, 'u', 'y', 'o', 'Z', 'B', 6853, 'y', 'U', 'n', 'W', 'd', 2125, '8421', '5767', 'P', 'y', 'k', 'U', '4099', '1639', 'M', '2415', '7821', '9365', 'O', 'r', '5485', 'J', '2813', 'k', '7481', '5221', '9233', 'O', 'u', 'X', 'E', 'U', 6691, 1867, 7289, 8993, 'K', 't', 'X', 5817, 'k', 3403]