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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Sun, 30 Sep 2012 00:08:03 -0600
Subject: Re: Should one always add super().__init__() to the __init__?
To: Python <python-list@python.org>
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Xref: csiph.com comp.lang.python:30543

On Sat, Sep 29, 2012 at 10:40 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> On Sat, 29 Sep 2012 17:51:29 -0400, Piet van Oostrum wrote:
>
>> It is not necesarily calling the parent class. It calls the initializer
>> of the next class in the MRO order and what class that is depends on the
>> actual multiple inheritance structure it is used in, which can depend on
>> subclasses that you don't know yet. This makes it even worse.
>
> I don't quite follow you here. It sounds like you are saying that if you
> have these classes:
>
> # pre-existing classes
> class A(object): pass
> class B(object): pass
>
> # your class
> class C(A, B): pass
>
> and somebody subclasses A or B, the MRO of C will change. That is not
> actually the case as far as I can see.

The MRO of C will not change, but the class that follows C may be
different in the MRO of a subclass.