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Python Object-Oriented Python Instant Objects Master Class

Posted by Adam Gataev
Adam Gataev
9,633 Points

OK, now let's add a method named run_lap. It'll take a length argument. It should reduce the fuel_remaining attribute by

I dont know why it doesnt work pls help me. OK, let's combine everything we've done so far into one challenge!

First, create a class named RaceCar. In the init for the class, take arguments for color and fuel_remaining. Be sure to set these as attributes on the instance. Also, use setattr to take any other keyword arguments that come in.

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

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

2 Answers

Antonio Falcetta
Antonio Falcetta
14,192 Points
Antonio Falcetta
Antonio Falcetta
14,192 Points 
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, lenght):
        # self.length = length  (REMOVE)
        self.fuel_remaining -= lenght * 0.125
        self.laps += 1
Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

It will work that way, by making the misspelling consistent. But wouldn't it be nicer to spell "length" correctly?

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

Here's a few hints:

  • "lenght" should be spelled "length"
  • you don't need to store "length" itself
  • to access instance variables (such as "laps"), you need to prefix their names with "self."