In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[8793, 'B', 3885, '8121', '4629', 'J', '921', 'H', 'H', 'J', '7717', '2203', 'O', 'I', 2433, 6533, 4631, 657], [2509, 2543, 's', 'P', 1147, 435, 'm', 1977, '8121', '4629', 'J', '921', 'H', 'H', 'J', '7717', '2203', 's', 'V', 'A']