In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['b', 997, 'u', 1919, 85, 'p', 1415, 'n', 'V', '7239', 'G', '909', '1983', 't', '4741', '7643', 'I', 'N', 'n', 9017, 1431, 'L', 3391, 'p', 'C'], [8803, 'V', 'c', 9353, 5373, 'n', 'V', '7239', 'G', '909', '1983', 't', '4741', '7643', 'T', 73, 8427, 2121, 'k']