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Python Object-Oriented Python Instant Objects Master Class

fuel_remaining isnt changing (wrong scope??)


I'm stuck on this assignment, I don't really understand how to get certain variables I guess. It seems I can't change fuel_remaining, it always stays the same and I'm wondering what I'm doing wrong.

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):
        RaceCar.laps += 1
        self.fuel_remaining = (length * 0.125)

1 Answer

Jennifer Nordell
Jennifer Nordell
Treehouse Teacher

Hi there, Marco Koopman! You're doing terrific and you clearly understand how to set the value of a variable. But you forgot something tiny here (you're literally off by one character). Every time we run a lap we want to reduce the amount of fuel remaining by a certain amount. Makes sense, right? We run a lap and now we have less fuel. Each time you run a lap, you're setting the fuel_remaining to the same number so it never changes.

You wrote:

self.fuel_remaining = (length * 0.125)

But you meant to write:

self.fuel_remaining = self.fuel_remaining - (length * 0.125)

Or in shorthand:

self.fuel_remaining -= (length * 0.125)

These will reduce the amount of fuel remaining and set the fuel_remaining value to the now reduced value.

Hope this helps! :sparkles: