In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[2623, 909, 1341, 'q', 7775, 'g', 5127, 'u', 1639, 'h', '823', 's', '749', 'N', '1009', '3319', 'y', '3739', 'X', 7875, 'L', 'x', 1457, 1637, 7795], [6389, 6789, 8803, 'h', '823', 's', '749', 'N', '1009', '3319', 'y', '3739', 'P', 6279, 4801, 'k', 'm']