old_contents: from attachment import Element
  
  required_properties = {
      'price',
  }
  
  
  class ReceiptElement(Element):
  
      def __init__(self, quantity=None, price=None, 
                         currency="CAD", **kwargs):
  
          self.kwargs = kwargs
          super(ReceiptElement, self).__init__(**self.kwargs)
          
          if price is None:
                  raise ValueError("Incorrect keyword-argument given for type ReceiptElement, needed: price") 
          
          self.quantity = quantity
          self.price = price
          self.currency = currency
  
  
      def to_json(self):
  
          payload = {
              'title': self.title,
              'subtitle': self.subtitle,
              'quantity': self.quantity,
              'price': self.price,
              'currency': self.currency,
              'image_url': self.image_url
          }
  
          return payload
  
new_contents: from attachment import Element
  
  required_properties = {
      'price',
  }
  
  
  class ReceiptElement(Element):
  
      def __init__(self, quantity=None, price=None, 
                         currency="CAD", **kwargs):
  
          self.kwargs = kwargs
          super(ReceiptElement, self).__init__(**self.kwargs)
          
          if price is None:
              raise ValueError("Incorrect keyword-argument given for type ReceiptElement, needed: price") 
          
          self.quantity = quantity
          self.price = price
          self.currency = currency
  
  
      def to_json(self):
  
          payload = {
              'title': self.title,
              'subtitle': self.subtitle,
              'quantity': self.quantity,
              'price': self.price,
              'currency': self.currency,
              'image_url': self.image_url
          }
  
          return payload
  
subject: fix indentation