In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['u', 6949, 'r', 'b', 6307, 8571, 9241, '4137', 'k', '5089', 'u', '2883', '7111', '493', 'Y', 'c', '8887', 'S', 'e', '9045', 'I', '7269', '959', 'T', 5243, 'O', 9755, 'S', 'g', 'A', 4811, 7405, 4021, 'b', 'R'], [2411, 'r', 'c', 'o', 'U', 793, 'j', 2279, 3573, 'M', 'k', 'n', 341, 7779, 1959, '4137', 'k', '5089', 'u', '2883', '7111', '493', 'Y', 'c', '8887', 'S', 'e', '9045', 'I', '7269', '959', 'a', 'f', 7183, 8067, 1769, 4647, 5439, 'R']