In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['W', 'y', 'f', 103, '6905', 'e', '1983', '3807', 'Q', '937', '6641', 'h', '6767', 'u', 'M', '5883', '783', 'S', 'I', 5939, 't', 'I', 'J', 'z', 7861, 'c', 'Y', 'g', 'E', 'R'], ['i', 'H', '6905', 'e', '1983', '3807', 'Q', '937', '6641', 'h', '6767', 'u', 'M', '5883', '783', 'S', 'c', 1885, 'X', 'e', 'W', 'm', 3965, 'j', 'I']