input: Write a python function to find the intersection of two lists.
  assert intersection([1, 5, 8, 9, 10], [2, 3, 5, 8, 9, 10]) == [5, 8, 9, 10]
  assert intersection([1, 2, 3, 4], [2, 3, 4, 5, 6]) == [2, 3, 4]
  assert intersection([7, 8, 9], [10, 11, 12]) == []
output: def intersection(list1, list2):
      return list(set(list1) & set(list2))