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From: Lie Ryan <lie.1296@gmail.com>
Subject: Re: How to mix-in __getattr__ after the fact?
Date: Sat, 29 Oct 2011 13:26:31 +1100
References: <4630c4d0-86bc-4295-8bbb-6f58415191c8@v15g2000vbm.googlegroups.com> <4EAAF264.1050307@stoneleaf.us>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:15126

On 10/29/2011 05:20 AM, Ethan Furman wrote:
>
> Python only looks up __xxx__ methods in new-style classes on the class
> itself, not on the instances.
>
> So this works:
>
> 8<----------------------------------------------------------------
> class Cow(object):
> pass
>
> def attrgetter(self, a):
> print "CAUGHT: Attempting to get attribute", a
>
> bessie = Cow()
>
> Cow.__getattr__ = attrgetter
>
> print bessie.milk
> 8<----------------------------------------------------------------

a minor modification might be useful:

bessie = Cow()
bessie.__class__.__getattr__ = attrgetter