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Date: Tue, 23 Jun 2015 17:21:55 -0700
Subject: Looking up a dictionary _key_ by key?
From: Dan Stromberg <drsalists@gmail.com>
To: Python List <python-list@python.org>
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Xref: csiph.com comp.lang.python:93052

I know that sounds strange: usually we look up values by key, not keys.

But suppose you have a strange key type that despite being "equal", is
not identical in some fields, and you need to see those fields.

Is there a way of getting the key used by the dictionary, short of
storing a reference to it in the value, or using a second dictionary?

Thanks!