In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['L', 'U', 7973, 'w', 'U', '5687', '7089', '7225', 't', '4623', '4019', 'Y', 'r', 'j', 'a', '2031', 'L', '5401', '143', 'E', 5489, 237], [337, 'z', 4259, 'H', 'T', 'X', 'R', 929, 8173, 1425, 'U', '5687', '7089', '7225', 't', '4623', '4019', 'Y', 'r', 'j', 'a', '2031', 'L', '5401', '143', 'C', 'U', 549, 'Z', 8167, 'M', 'e', 1749, 2909, 'U', 2321]