In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[6381, 'b', 3719, 'S', '6559', 'y', 't', 'g', 'o', 'U', 'X', '8205', '7697', '3193', 'H', '4859', '9431', 'Q', 4877, 'Y', 'X', 6521, 'u', 8583, 'p', 9943, 'c', 'D', 5127, 'f', 'T'], ['X', 2289, 2081, 'X', 'L', 'S', '6559', 'y', 't', 'g', 'o', 'U', 'X', '8205', '7697', '3193', 'H', '4859', '9431', 's', 'C', 'b', 3649, 9081, 4879, 'P', 'L', 'S', 9993, 6717, 'o', 7487]