text: 
  
  # noinspection PyUnusedLocal
  # skus = unicode string
  from .product import create_products
  from .promotion import create_promotions
  from .basket import Basket
  
  def checkout(skus):
  
      try:
          products = create_products(skus)
      except KeyError:
          return -1
      promotions = create_promotions()
  
      basket = Basket(products, promotions)
      print('products before', basket.products)
      basket.calculate_free()
      print('products after', basket.products)
  
      
      return basket.get_total_price
  
      
  
  