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Python Object-Oriented Python Instant Objects Master Class

Posted by Bhargav Chava
Bhargav Chava
1,706 Points

whats wrong in this

Challenge Task 2 of 3

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:
    laps=0
    def __init__(self,color,fuel_remaining,**args):
        self.color=color
        self.fuel_remaining=fuel_remaining
        for n,v in args.items():
            setattr(self,n,v)
    def run_lap(length):
        fuel_remaining=fuel_remaining-(length*0.125)
        laps+=1

2 Answers

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! Although the challenge doesn't explicitly say it, this method will need to also take an instance of self. You should access the properties through the dot notation such as self.fuel_remaining and self.laps. Hope this helps, but let me know if you're still stuck! :sparkles:

Bhargav Chava
Bhargav Chava
1,706 Points

no it doesn't work

Bhargav Chava
Bhargav Chava
1,706 Points 
class RaceCar:
    laps=0
    def __init__(self,color,fuel_remaining,**args):
        self.color=color
        self.fuel_remaining=fuel_remaining
        for n,v in args.items():
            setattr(self,n,v)
    def run_lap(self,length):
        self.fuel_remaining=self.fuel_remaining-(self.length*0.125)
        self.laps+=1

Moderator edited: Added markdown so the code renders properly in the forums.

Jennifer Nordell
seal-mask
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Bhargav Chava I apologize for the delay in getting back to you. It's really close to being correct now. The length variable is not a property of this class, so self.length is not valid. If I remove the self from self.length, your code passes step 2. Hope this helps! :sparkles:

Ingrid Marquez
PLUS
Ingrid Marquez
Courses Plus Student 1,032 Points
Ingrid Marquez
Ingrid Marquez
Courses Plus Student 1,032 Points

How about this? What's wrong with the run_lap method? I keep getting '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):
        self.length = length
        self.fuel_remaining = self.fuel_remaining - (length * 0.125)
        self.laps = laps + 1