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Python

Posted by Michael Anders
Michael Anders
4,489 Points

frustration.py passing but do not understand why

I like doing all my coding and testing in ipython. So I came up with this

Creating class 

In [87]: class Liar(list):
    ...:     real_length = []
    ...:     def __len__(self, real_length):
    ...:         real_length = super().__len__()
    ...:         return real_length + 3
    ...:

Instantiating

In [88]: x = Liar()

I was looking inside the object (omitting output)

In [89]: dir(x)

showing empty list based on "real_length" variable

In [90]: x.real_length
Out[90]: []

appending item to list

In [91]: x.real_length.append('dog')

showing what is in the list

In [93]: x.real_length
Out[93]: ['dog']

Getting the list length ( I should expect 4 since I add 3 and there is already one item) 

In [95]: x.real_length.__len__()
Out[95]: 1

My questions is: Why does this pass the challenge if it fails here? I "passed" the challenge but do not understand why. Thanks in advance!