In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[7839, 'u', 1477, 'S', 'Y', '9267', 'd', 'D', 'r', '4665', 'b', '441', '7649', 'h', 'C', 'J', 6757, 6757, 'W', 'E'], [2981, 8951, 2897, 'c', 'M', 9009, 'w', 'E', 'F', 321, 9155, 'Y', '9267', 'd', 'D', 'r', '4665', 'b', '441', '7649', 'h', 'C', 'W', 3117, 'K', 5559, 7379, 'S']