In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['k', 3235, 'I', 'I', 8907, 's', 3067, 'U', 1869, 'X', 'j', 'W', '5163', '4497', '4059', '1193', '3755', '6607', '8337', '6861', 'f', 'S'], [7557, 4497, 8569, 'Z', 6271, 3363, 9981, 'r', 5929, 5639, 'X', 'j', 'W', '5163', '4497', '4059', '1193', '3755', '6607', '8337', '6861', 'b', 'D']