input: Write a function to create a loop in Python that prints each item of the given list with a message. If the list is empty, print "The list is empty." 
  assert print_list(['A', 'B', 'C', 'D'])
  # Output:
  # The item is: A
  # The item is: B
  # The item is: C
  # The item is: D
  assert print_list([])
  # Output:
  # The list is empty.
output: def print_list(lst):
      if not lst:
          print("The list is empty.")
      else:
          for item in lst:
              print(f"The item is: {item}")