In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[7783, 1529, 'X', 'j', 'Y', 'y', 'u', '291', 'y', 'U', 'm', 'u', 'y', 'g', 'v', '2493', '7113', '1541', 'x', 'R', 9603, 'W', 3987, 'f', 'S'], [3501, 2705, 3909, 889, 2733, 2319, 5435, 'P', 'a', 3391, 'y', 'u', '291', 'y', 'U', 'm', 'u', 'y', 'g', 'v', '2493', '7113', '1541', 'Q', 7965, 'Z', 'J', 'm', 8597]