In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
Q: [4339, 'i', 7857, 315, 'W', '3573', '689', 'y', '9557', 'J', 'b', '2185', 'i', 7649, 'F', 'g', 6973], ['r', 5097, 5467, 't', 'N', 'Y', 'W', '3573', '689', 'y', '9557', 'J', 'b', '2185', 'l', 837, 643, 2055, 'J', 'I']
A: 
W, 3573, 689, y, 9557, J, b, 2185