(20 points) Write a recursive Python function that takes as input two sorted lists of numbers and returns a sorted union of the two input lists. For example, union([1,5,10,20], [2,4,10] returns[1,2,4,5,10,10,20] The function should look like this: # Input A and B are both sorted lists # Output C is sorted and is a union of A and B def union(A, B) # your code goes here return C