In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['U', 233, 'S', 7929, 'e', 'I', 'x', 'Q', 'O', 'Y'], ['X', 8175, 317, 6951, 'e', 'I', 'x', 'Q', 'Q', 'U']