input: Write a python function to process a list of data using multiprocessing.
  assert process_list_data([1, 2, 3, 4, 5]) is None
  assert process_list_data([10, 20, 30, 40, 50]) is None
  assert process_list_data([]) is None
output: def process_list_data(data):
      import multiprocessing
  
      def process_item(item):
          print(f"Processing item: {item}")
  
      if not data:
          return
  
      with multiprocessing.Pool() as pool:
          pool.map(process_item, data)