In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[7671, 2025, 'n', 5487, 2017, 'W', 'W', 'P', 'J', 'l', 'd', '4887', 'U', 'i', '9793', 'w', 'n', '3337', '1051', '4477', 'Y', 'L', 6621, 'e', 3435, 3309, 'H', 6359], ['q', 'L', 'c', 'l', 'b', 'y', 'W', 6723, 'd', '4887', 'U', 'i', '9793', 'w', 'n', '3337', '1051', '4477', 'Y', 'J', 'L']