code: def subscription(self):
  		
  
  		subscriptions = self.valid_subscriptions
  
  		if subscriptions.count() > 1:
  			raise MultipleSubscriptionException(
  				"This customer has multiple subscriptions. Use Customer.subscriptions "
  				"to access them."
  			)
  		else:
  			return subscriptions.first()
docs: Shortcut to get this customer's subscription.
  
  		:returns: None if the customer has no subscriptions, the subscription if
  			the customer has a subscription.
  		:raises MultipleSubscriptionException: Raised if the customer has multiple subscriptions.
  			In this case, use ``Customer.subscriptions`` instead.