In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['B', 5209, 3909, 'U', '349', '1837', '263', '1411', 'C', 'C', 'b', '9005', '4293', '677', 'S', '6373', 'Q', '9689', 'r', 'd', 'W', 9655, 4973], ['h', 'x', 5547, 8317, 6629, 'B', 8439, 'U', '349', '1837', '263', '1411', 'C', 'C', 'b', '9005', '4293', '677', 'S', '6373', 'Q', '9689', 'z', 4107, 555, 'd', 7953, 'u']