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Python Object-Oriented Python Advanced Objects Frustration

Tobiasz Lorenc
Tobiasz Lorenc
3,757 Points

__len__ problem, help me

Now I want you to make a subclass of list. Name it Liar.

Override the len method so that it always returns the wrong number of items in the list. For example, if a list has 5 members, the Liar class might say it has 8 or 2.

You'll probably need super() for this.

import random

class Liar(list):
    def __len__(self, other):
        return self# + bool(random.randint(-2, 2))

Bot answer: Bummer: TypeError: len() missing 1 required positional argument: 'other'

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

You are on the right track.

  • the __len__ method doesn’t take arguments so only self is needed on the def line, and no arguments are needed in the super call.
  • the results of the super call are not saved
  • modify the results from super call and return it.

Post back if you need more help. Good luck!!!