def sell(self, stock_set_id, num_of_units): if not self.acct: raise NoAccountSelectedError("No account selected") try: stock = Stock_Owned.get(id=stock_set_id) except Stock_Owned.DoesNotExist as e: raise e # Try to Sell Stock try: self.acct.sell_stock(stock, num_of_units) except StockNotOwnedError as e: raise e