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danielchristie
21,505 Pointsh
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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(length):
fuel_remaining - length * 0.125
laps += 1
3 Answers

Steven Parker
216,057 PointsIt would help if you were to explain your issue.
But I noticed a few things right off, when you subtract from the fuel_remaining the result isn't being stored. You probably want to use a subtraction assigment operator there ("-=").
Also, your run_lap method should have self as the first argument, which you would also use to prefix the names of the the instance variables ("self.fuel_remaining" and "self.laps").

Gabriel Santos
4,113 PointsPlease state the issue :O def run_lap(length): fuel_remaining -= length * 0.125 <--assign it to the variable laps += 1

sankalp yadav
2,101 PointsTry this, it will help . never write laps = laps +1 it is not good use or design.
```class RaceCar:
def __init__(self,color,fuel_remaining,laps = 0,**kwargs):
self.color = color
self.fuel_remaining = fuel_remaining
self.laps= laps
for k,v in kwargs.items():
setattr(self,k,v)
def run_lap(self,length):
self.fuel_remaining = self.fuel_remaining -(length*0.125)
self.laps = self.laps + 1
```