Passing in a new value to each key using Python's `dict.fromkeys`

Question

How can I get around this limitation:

>>> test_dict = dict.fromkeys(['k1', 'k2'], dict())
>>> test_dict['k1']['sub-k1'] = 'apples'
>>> test_dict
{'k2': {'sub-k1': 'apples'}, 'k1': {'sub-k1': 'apples'}}

I want each of the keys k1 and k2 to have a new dictionary instance, not the same one.

score 4 · Accepted Answer · answered Mar 28 '12 at 20:08

4

Then don't give them the same instance of the object.

test_dict = dict((x, dict()) for x in ['k1', 'k2'])

answered Mar 28 '12 at 20:08

Ignacio Vazquez-Abrams

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Apparently there is no way to pass an expression to `dict.fromkeys`. Thanks. – sholsapp Mar 28 '12 at 20:11

Passing in a new value to each key using Python's `dict.fromkeys`

1 Answers1