In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['s', 6663, 'c', 3323, 9301, 'I', 8947, 'F', 'l', 'f', 6185, 'k', 'S', 'P', '7291', 'W', '9037', '6543', '9801', 'b', 'q', '1781', '6399', 'x', 'w', 'x', '803', '3491', '9965', '5911', 'y', '7699', '8789', '8415', '4483', 'm', '8503', '2553', 'n', 'p', 1877, 'V', 4415, 6323, 'Y', 8461, 9691, 'l', 'f', 5237, 'f', 'Z', 'g', 'B', 9173, 549, 'h', 3595, 'M', 'F', 1215, 'v', 1433, 5261], [8455, 'X', 5657, 'm', 2703, 'k', 'S', 'P', '7291', 'W', '9037', '6543', '9801', 'b', 'q', '1781', '6399', 'x', 'w', 'x', '803', '3491', '9965', '5911', 'y', '7699', '8789', '8415', '4483', 'm', '8503', '2553', 'n', 'C', 'n', 't', 4557, 'R', 'a', 'R', 6821, 'f', 5003, 6499]