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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 6 Apr 2011 14:08:45 -0600
Subject: Re: a better way to invert a list?
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On Wed, Apr 6, 2011 at 1:51 PM, Paul Rubin <no.email@nospam.invalid> wrote:
> =A0 =A0In Haskell or ML, you can use patterns that contain wild
> =A0 =A0cards that play a role in the pattern-matching but don't establish=
 any
> =A0 =A0binding. Can that be done in Python?
>
> Not as much. =A0You could say something like
>
> =A0 =A0 =A0 =A0 sorted(enumerate(p), key=3Dlambda(_,j): j)
>
> which gets the meaning across (it binds the symbol "_" though this
> doesn't escape the lambda).

That will just give you a SyntaxError.  Implicit tuple unpacking was
removed in Python 3.  It has to be done with an explicit assignment
statement now.