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Date: Mon, 24 Sep 2012 08:30:33 +1000
Subject: Re: List Problem
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:29866

On Mon, Sep 24, 2012 at 8:27 AM, Chris Angelico <rosuav@gmail.com> wrote:
> a = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
> b = deepcopy(a) # b is a new list with three new sublists
>

Oops, this should be:

b = copy.deepcopy(a)

as in Steven's post. And in case I wasn't clear about it, the
deepcopy() function does deal with the issue I mention, but that's
part of why it's an expensive operation.

ChrisA