In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['n', 7925, 'Q', 'L', 'X', 1933, 'X', 'U', '2687', '9369', '87', 'Q', '7541', 'x', 't', 'l', 't', 'J', 1347, 'z', 'u', 'e', 'Q', 'k', 8309, 2817, 'P'], ['N', 'X', 5261, 7879, 'X', 'U', '2687', '9369', '87', 'Q', '7541', 'x', 't', 'l', 't', 'B', 8419, 6935, 'J', 235, 'T', 7057, 1599, 1537, 'v']