In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['v', 5723, 253, 1123, 7869, 7155, 'D', 1883, 4223, 'p', 'b', '9525', 'd', '8885', 'L', 'h', '4175', 'l', '4611', '2859', '8319', '8505', 'z', '7905', 'k', 'l', 6901, 9339, 'B', 'z', 'N', 'O', 6983], ['u', 'x', 6991, '9525', 'd', '8885', 'L', 'h', '4175', 'l', '4611', '2859', '8319', '8505', 'z', '7905', 'm', 'g', 397, 1681, 4589, 5203, 'x']