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Python Object-Oriented Python Instant Objects Master Class

Suraj Shah
Suraj Shah
1,055 Points
Posted by Suraj Shah
Suraj Shah
1,055 Points

I get a bummer error when trying to solve this challenge. I am a struggling with adding a lap counter.

Challenge is: 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:
    laps = 0

    def __init__(self, color, fuel_remaining, **kwargs):
        self.color = color
        self.fuel_remaining = fuel_remaining
        for attribute, value in kwargs.items():
            setattr(self, attribute, value)

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

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

You are very close! The method run_lap does not need the parameter laps in its signature definition.

Matthew Earlywine
Matthew Earlywine
3,508 Points

My solution was the same but I am still getting an error

class RaceCar:
    laps = 0

    def __init__(self, color, fuel_remaining, **kwargs):
        self.color = color
        self.fuel_remaining = fuel_remaining
        for attribute, value in kwargs.items():
            setattr(self, attribute, value)

    def run_lap(self, length, laps):
        self.fuel_remaining = self.fuel_remaining - (length * 0.125)
        self.laps = self.laps + 1
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Matthew, you are close! Remove the laps parameter from the run_lap method definition

Nick Kolarik
Nick Kolarik
3,747 Points
Nick Kolarik
Nick Kolarik
3,747 Points

This also results in "Bummer: Try again!" but works on my machine in an IDE...

class RaceCar:

    def __init__(self, color, fuel_remaining, laps = 0, **kwargs):
        self.color = color
        self.fuel_remaining = fuel_remaining
        self.laps = laps

        for key, value in kwargs.items():
            setattr(self, key, value)

    def run_lap(self, length):
        self.fuel_remaining -= length * 0.125
        self.laps += 1
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

Looks like you're mixing spaces and tabs. Best to stick to all-space indentation! Good luck!!