def hotel_cost(nights):     hotel_cost = (nights * 140)     return hotel_cost  def plane_ride_cost(city):     if city == "Charlotte":         return 183     elif city == "Tampa":         return 220     elif city == "Pittsburgh":         return 222     elif city == "Los Angeles":         return 475     return city  def rental_car_cost(days):     rental_car = days * 40     if (days >= 7):         return (rental_car - 50)     elif (days >= 3):         return (rental_car - 20)     else:         return rental_car