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Python Object-Oriented Python Instant Objects Master Class

Travis John Villanueva
Travis John Villanueva
5,052 Points
Posted by Travis John Villanueva
Travis John Villanueva
5,052 Points

Master Class 2/3

Ive tried and i dont know where is that bug.

  1. created a method run lap with length argument- Done
  2. decrease the fuel remaining by length * .125 - Done
  3. increment laps by 1 every time run_lap is called - Done

Im not sure do i need a return for it?

racecar.py 
class RaceCar:
    color=""
    fuel_remaining=0
    laps=0



    def __init__(self, color, fuel_remaining, **kwargs):
        self.color=color
        self.fuel_remaining = fuel_remaining
        self.laps = 0

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

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

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

The challenge doesn't require the method to return anything, you could but it's generally better to only do what the challenge asks for. However, I don't think you can make an assignment in a "return" statement.

Also, you may be expecting that "and" syntax to do something other than what it really does. Those two assignments should be separate statements.

Travis John Villanueva
Travis John Villanueva
5,052 Points
Travis John Villanueva
Travis John Villanueva
5,052 Points

Hi Steven,

First of all, thank you for your prompt reply. It is Sunday here in Sydney and i salute you for answering me. Originally here is my code:

class RaceCar: color="" fuel_remaining=0 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 -= length * 0.125 self.laps += 1

i was really on a hit and miss after this didnt work

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

It's hard to tell without Markdown formatting, so it could be you had an indentation error. But if your "run_lap" method is structured like this, it should pass the challenge:

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

In future postings, use the instructions for code formatting in the Markdown Cheatsheet pop-up below the "Add an Answer" area. :arrow_heading_down:   Or watch this video on code formatting.

Pitrov Secondary
Pitrov Secondary
5,121 Points
Pitrov Secondary
Pitrov Secondary
5,121 Points

Hi. Why do I have to do self.fuel_remaining and not just fuel_remaining? Because in the init I did self.fuel_remaining = fuel_remaining so that I could call it with fuel_remaining without the self.

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

I think you're misinterpreting what that line does. self.fuel_remaining = fuel_remaining just takes the value that was passed in through the parameter named "fuel_remainng" and assigns that value to the class field variable "self.fuel_remaining". You still need the "self." part to refer to that variable.