input: Write a python function to combine two lists and sort the resulting list in ascending order.
  assert combine_and_sort([3, 1, 4], [2, 5, 6]) == [1, 2, 3, 4, 5, 6]
  assert combine_and_sort([10, 9, 8], [7, 11, 12]) == [7, 8, 9, 10, 11, 12]
  assert combine_and_sort([0], [0]) == [0, 0]
output: def combine_and_sort(list1, list2):
      combined_list = list1 + list2
      combined_list.sort()
      return combined_list