For some reason this isnt working

```
def hotel_cost(nights):
return 140 * nights
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 ("Nothing Defined")
def rental_car_cost(days):
cost = days * 40
if days >= 3 and days < 7:
cost -= 20
elif days >= 7:
cost -= 50
return cost
def trip_cost(city, days):
return rental_car_cost(days) + plane_ride_cost(city) + hotel_cost(days - 1)
```