In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['L', 3235, 6117, 529, 3387, 'n', 'H', 3047, 'b', '8499', '671', '6951', '4059', '3473', 'P', 'V', 'a', 4015, 'p', 'U', 'A', 'K', 'i', 619], [8321, 8173, 2453, 'b', '8499', '671', '6951', '4059', '3473', 'P', 'V', 'J', 'D', 6853, 'A', 'I', 8391]