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Python Object-Oriented Python Instant Objects Master Class

HARPREET SINGH
HARPREET SINGH
146 Points
Posted by HARPREET SINGH
HARPREET SINGH
146 Points

How to initialize laps to 0

Ho wto initialise laps to 0

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, length):
        self.fuel_remaining -=  0.125*self.length
        self.lap += 1

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The initialization is OK for task 2, but:

  • "length" is a parameter, so it should not have the "self." prefix added to it
  • the last line of the method is incrementing "lap" instead of "laps" (with an "s')
HARPREET SINGH
HARPREET SINGH
146 Points
HARPREET SINGH
HARPREET SINGH
146 Points

any write up where I can get more clarity on "why length, which is parameter here does not require "self" prefix". I still need to get more understanding on same.

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The "self" prefix represents the object itself and is used to refer to instance variables that are stored inside the object, such as "laps".

But "length" is the name of a parameter that is passed to the method, and isn't stored (it will go away when the method ends). So you reference it by name without any prefix.