input: Write a function to subtract elements of two lists using map and lambda functions.
  assert sub_list([1, 2, 3], [4, 5, 6]) == [-3, -3, -3]
  assert sub_list([1, 2], [3, 4]) == [-2, -2]
  assert sub_list([90, 120], [50, 70]) == [40, 50]
output: def sub_list(list1, list2):
      return list(map(lambda x, y: x - y, list1, list2))