In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['s', 5761, '6671', 'C', '913', '9413', '3523', 'U', '6719', 'n', '7221', 'M', 4077, 5491, 5965, 'P', 'n'], ['B', 'q', 9697, 9271, 'P', 'Z', 'C', '6671', 'C', '913', '9413', '3523', 'U', '6719', 'n', '7221', 'W', 'K', 8987, 'j', 8785, 6709]