My Vacation: Codecademy Course - Functions

def hotel_cost(nights):
    return nights * 140

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
     else:
        return "I didn't understand you!"

def rental_car_cost(days):
    cost = days * 40
    if days >= 7:
        return cost - 50
    elif days >= 3:
        return cost - 20
    else:
        return cost
def trip_cost(city,days):
    return int(rental_car_cost(days)) + int(hotel_cost(days)) + int(plane_ride_cost(city))