<s> class PaymentProvider ( object ) : <EOL> def get_start_payment_form ( self , request , order ) : <EOL> raise NotImplementedError ( ) <EOL> def get_order_id ( self , notification_request ) : <EOL> raise NotImplementedError ( ) <EOL> def get_transaction_id ( self , notification_request ) : <EOL> raise NotImplementedError ( ) <EOL> def get_cart_id ( self , notification_request ) : <EOL> raise NotImplementedError ( ) </s>
