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Date: Mon, 03 Nov 2014 12:04:48 +0100
From: Antoon Pardon <antoon.pardon@rece.vub.ac.be>
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To: Pyton List <python-list@python.org>
Subject: Dictionaries with variable default.
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Xref: csiph.com comp.lang.python:80150

Is it possible to have a default dictionary where the default is dependant
on the key?

I was hoping something like this might work:
>>> m = defaultdict(lambda key: key+1)

But it obviously doesn't:
>>> m[3]

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: <lambda>() takes exactly 1 argument (0 given)

-- 
Antoon Pardon