input: Write a function to print each item of a given list with a message that says "The item is: {item}". If the given list is empty, the function should print "The list is empty."
  assert print_items(['A', 'B', 'C', 'D'])
  assert print_items([])
  
  Expected output:
  for item in ['A', 'B', 'C', 'D']:
      print("The item is: {}".format(item))
  print("The list is empty.")
output: def print_items(lst):
      if lst:
          for item in lst:
              print(f"The item is: {item}")
      else:
          print("The list is empty.")