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Python: Dictionaries with variable default

+2 votes
333 views

Is it possible to have a default dictionary where the default is dependent 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 "", line 1, in 
TypeError: () takes exactly 1 argument (0 given)
posted Nov 3, 2014 by anonymous

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