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Python Object-Oriented Python Instant Objects Master Class

Posted by YZ L
YZ L
6,184 Points

I'm stuck on the challenge

Vrroom!

OK, now let's add a method named run_lap. It'll take a length argument. It should reduce the fuel_remaining attribute by length multiplied by 0.125.

Oh, and add a laps attribute to the class, set to 0, and increment it each time the run_lap method is called.

racecar.py 
class RaceCar:
    def __init__(self,color,fuel_remaining,laps=0,**kwargs):
        self.laps = laps
        self.color = color
        self.fuel_remaining = fuel_remaining
        for key, value in kwargs.items():
            setattr(self, key, value)

    def run_lap(self,length):
        fuel_remaining = (fuel_remaining - length) * 0.125 
        laps = laps + 1

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

You are very close. Three errors to fix:

  • fuel_remaining is an attribute of the instance and should be referenced with self.fuel_remaining
  • laps is also an attribute and should be referenced with self.fuel remaining
  • the math on calculating self.fuel_remaining is incorrect. Currently you are setting it to the difference between length and fuel_remaining multiplied by 0.25. Instead, subtract the product of the length and 0.25

Post back if you need more help. Good luck!!