In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['K', 2461, 'U', 4547, 6687, 'z', 'q', 'S', 'A', 'S', 'I', 'H', 'Z', '3695', 'D', '8187', '9463', '4049', 'q', 'U', '6859', 'l', 'J', 'G', 'P', 'k', 'Z', 'B', 'K', 'Q', 'D', 7725, 273, 'Q', 'I', 'K', 6839, 419, 7801, 'H', 3753, 8471, 'y'], ['t', 'k', 'p', 6027, 'r', 'I', 'H', 'Z', '3695', 'D', '8187', '9463', '4049', 'q', 'U', '6859', 'l', 'J', 'G', 'P', 'k', 'Z', 'B', 'Q', 'a']