In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[6917, 7141, '3657', '9205', 'b', 'm', 'Q', 'g', 'q', 'l'], [1429, 7173, 3447, '3657', '9205', 'b', 'm', 'Q', 'U', 'f']