def save(self, db: DBManager):
if self._id:
order = db.get_order(self._id)
order.is_current = self.is_current
order.product_id = self.product_id
order.quantity = self.quantity
db.save_element(order)
else:
db.save_element(self.get_order())
def delete(self, db: DBManager):
if self._id:
order = db.get_order(self._id)
db.delete_element(order)