In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[8191, 6935, 3623, 'D', 6189, 'M', 4569, 6755, 'x', '3525', '1359', '6459', '6685', '6407', '6689', 'H', 'F', 'W', 'l', 't', 9383, 417, 1573], [9671, 'H', 'J', 'M', 'M', 'x', '3525', '1359', '6459', '6685', '6407', '6689', 'H', 'p', 2083, 'w', 767, 5767, 'S', 'X', 'L']