You will be given a definition of a task first, then some input of the task.
In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.

['w', 'a', 'o', '421', 'a', 'z', 'Y', 'U'], ['l', 'B', 'g', 'o', '421', 'a', 'I', 'i']
Output:
o, 421, a