In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[4907, 'B', 'o', 281, 2193, 9213, '951', '951', 'L', '3293', '4835', 'W', 'R', '6981', '3079', '2739', '1841', 't', 'b'], [3483, 7825, 4807, 1289, 5947, '951', '951', 'L', '3293', '4835', 'W', 'R', '6981', '3079', '2739', '1841', 'u', 'D', 'z', 'i', 6969, 4031, 'X', 'B']