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Python Object-Oriented Python Instant Objects Master Class

Marcus De Silva
Marcus De Silva
1,717 Points

Method not working


I'm not sure what I am missing here, I had this working, but I lost my progress and had to start over. Unfortunately, all I get is "bummer: Try again!"

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

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

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

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,033 Points

Hey Marcus De Silva, you are very close! The following needs fixing:

:point_right: since laps is an instance attribute, it is referenced using self.laps

:point_right: the attribute self.fuel_remaining needs to be updated. Maybe try -= instead of -

:point_right: no value needs to be returned from the method. So the return can be removed

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

Marcus De Silva
Marcus De Silva
1,717 Points

Hi Chris!

Thank you very much for your help. I'm still having some trouble knowing when to use the 'self', but I think I'm getting better with it. Have a great day!

Chris Freeman
Chris Freeman
Treehouse Moderator 68,033 Points

Use self. when you want to refer to an attribute within the same instance. Other non-attributes are simply regular local variables.