input: Write a function to take a list of strings as input and print the strings in alphabetical order. If the list is empty, do nothing.
  assert sort_and_print(["cat", "dog", "apple", "banana"])==None
  assert sort_and_print(["zebra", "ant", "frog", "bird"])==None
  assert sort_and_print([])==None
output: def sort_and_print(strings):
      if strings:
          strings.sort()
          for s in strings:
              print(s)