In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['s', 977, 6423, 4851, '3141', 'Q', '25', '8795', 'Q', 'f', 1879], [7717, 1801, 5329, 'V', '3141', 'Q', '25', '8795', 'Q', 'l', 6703]