In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[6423, 'w', 'K', 'm', 'S', 'X', '8857', 'r', '9809', 'a', 'g', '7297', 'H', 'Q', 'W', 'I', 'm', '3277', 'm', 'W', 'L', 'H', 'S', 'X', 'y', 2479, 'p', 'B', 7193, 8327, 'X', 8547, 2261, 'X', 477, 535, 'w', 'f', 2923], [5389, 6751, 'F', 'l', 9579, 'A', 'S', 'X', '8857', 'r', '9809', 'a', 'g', '7297', 'H', 'Q', 'W', 'I', 'm', '3277', 'm', 'W', 'L', 'H', 'O', 't', 8821, 'H', 3919, 7667, 'x', 'v', 4035, 3179, 9235, 5679, 'c', 'P']