In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[3203, 'y', 'l', 'U', 'H', 9217, 'I', 'k', 'U', 6537, 'U', 4967, 't', '7075', 'F', '481', 's', 'G', 'y', '2063', '1255', 'I', '5383', 'y', 'M', '2227', 'q', 'x', 'C', 1783, 'H'], [9873, 'p', 't', '7075', 'F', '481', 's', 'G', 'y', '2063', '1255', 'I', '5383', 'y', 'M', '2227', 'q', 'x', 'D', 8073, 4259, 3955, 'Q', 3733, 'A', 2541, 4423, 827, 291, 3905, 7567, 7967]