input: 
  def item_information(item) -> str:
      """Given an instance of StoreItem class, return the string representation 
      of the item with its name and price.
      >>> store_item = StoreItem(1, 'Book', 9.99, 'A good reading material.')
      >>> item_information(store_item) == 'Book, $9.99'
      True
      """
  
output:     return f"{item.name}, ${item.price:.2f}"