In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[9005, 6757, 'f', 'X', 'z', 8699, 8617, 'K', 1747, 7267, 'k', 5455, 845, '1867', 'f', '7909', 'v', 'j', '6857', 'R', 'H', 'G', '6843', 'y', '1477', 'K', 'r', '443', '9547', 'H', 'o', 'O', 'W', 'f'], [4767, 'v', 8311, 'B', 'l', 'K', 'a', 5661, 'f', '1867', 'f', '7909', 'v', 'j', '6857', 'R', 'H', 'G', '6843', 'y', '1477', 'K', 'r', '443', '9547', 'A', 4913, 7067, 'x', 417, 9149, 6475, 5647, 's']