In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[3807, 'Q', 'S', 3677, 'v', 3147, 'L', 'K', 715, '10005', '7209', 'r', '9205', '6193', 'f', '1005', '5085', '5543', 'S', 'L', 2973, 8809], ['x', 'v', 'b', 7635, 217, 'g', 3927, 3151, 't', 2375, '10005', '7209', 'r', '9205', '6193', 'f', '1005', '5085', '5543', 'S', 'r', 'P']