tps://www.codecademy.com/courses/python-beginner-P5YtY/1/3?curriculum_id=4f89dab3d788890003000096

File "python", line 18

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Below your existing code, define a function called rental_car_cost with an argument called days.

Calculate the cost of renting the car:

Every day you rent the car costs $40.

if you rent the car for 7 or more days, you get $50 off your total.

Alternatively (elif), if you rent the car for 3 or more days, you get $20 off your total.

You cannot get both of the above discounts.

Return that cost.

```
before_discount_cost = 0
def rental_car_cost(days):
days * 40 = before_discount_cost
if days >= 7:
return before_discount_cost - 50
elif days >= 3:
return before_discount_cost - 20
else :
return before_discount_cost
```