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Python Object-Oriented Python Advanced Objects Frustration

I don't understand where I'm getting this wrong

Override the len method so that it always returns the wrong number of items in the list.

frustration.py
import random

class Liar(list):
    def __len__(self):
        super().__len__(self)
        return self + bool(random.randint(-3, 3))

1 Answer

Steven Parker
Steven Parker
229,582 Points

The message "Bummer: TypeError: expected 0 arguments, got 1" is a clue that you're passing an argument to a method that doesn't take any. In this case, it's passing "self" to "__len__", since the "self" parameter is handled internally and isn't passed explicitly.

Also, your return calculation doesn't make sense, it's attemptling combine a list (self) with a boolean. But what's needed here is simple since you only want to be sure to always give a wrong length. So you might just return the actual length (obtained with "super") with some value (constant, no need for anything random) added to it.