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Date: Wed, 4 Apr 2012 01:09:35 +1000
Subject: Re: Is there a better way to do this snippet?
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:22607

On Wed, Apr 4, 2012 at 12:36 AM, python <w.g.sneddon@gmail.com> wrote:
> for item in tag23gr:
> ... =A0 =A0 value, key =3D tuple(item)
> ... =A0 =A0 if(g23tag.get(key)):
> ... =A0 =A0 =A0 =A0 =A0 =A0 g23tag[key].append(value)
> ... =A0 =A0 else:
> ... =A0 =A0 =A0 =A0 =A0 =A0 g23tag[key] =3D [value]

Simple enhancement: Use setdefault. Instead of the if, just use:

g23tag.setdefault(key,[]).append(value)

That'll cover both cases in one.

You can leave off the explicit tuple construction; if item is a
two-element list, you can unpack it directly. You can also embed that
straight into your for loop:

for value,key in tag23gr:

Do both and you cut your loop down to two lines. Cool! :)

Chris Angelico