`I have been stuck on this for days. I slept on this and found no answer in my head while away. I tried going for walks etc. The output for the error is:`

Traceback (most recent call last):File "python", line 17, in

NameError: name 'days' is not defined

`I thought days **is** defined since it was defined and a argument. Also I would like to properly link this as others have done with the numbers for each line of coding. How do I do that?`

def hotel_cost(days):

return 140 * days

def plane_ride_cost(city):

if city == "Charlotte":

return 183

if city == "Tampa":

return 220

if city == "Pittsburgh":

return 222

if city == "Los Angeles":

return 475

else:

return "Invalid Destination"

def rental_car_cost(days):

cost = days * 40

if days >= 7:

cost -= 50

elif days >= 3:

cost -= 20

def trip_cost(city, days):

return rental_car_cost(days)+plane_ride_cost(city)+hotel_cost(days)

print trip_cost(Tampa,10)