This is my code for this part. I get the error "It looks like rental_car_cost returns 120 instead of the correct amount (100) for 3 days."

```
def rental_car_cost(days):
return 40*days
if days >= 7:
return cost - 50
elif days >= 3 and days < 7:
return cost - 20
else:
return cost
```

Thanks!