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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Mon, 8 Oct 2012 13:42:08 -0600
Subject: Re: Insert item before each element of a list
To: Python <python-list@python.org>
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On Mon, Oct 8, 2012 at 1:28 PM,  <mooremathewl@gmail.com> wrote:
> What's the best way to accomplish this?  Am I over-complicating it?  My gut feeling is there is a better way than the following:
>
>>>> import itertools
>>>> x = [1, 2, 3]
>>>> y = list(itertools.chain.from_iterable(('insertme', x[i]) for i in range(len(x))))
>>>> y
> ['insertme', 1, 'insertme', 2, 'insertme', 3]
>
> I appreciate any and all feedback.

Using the "roundrobin" recipe from the itertools documentation:

x = [1, 2, 3]
y = list(roundrobin(itertools.repeat('insertme', len(x)), x))