CODEWITHSUNDEEP
pythonpython-2.7dictionary
maazza
maazza

Reputation: 7183

Correct way to declare a defaultdict

I am currently trying to use a defaultdict in a unittest. I declare it this way.

dic_response = defaultdict(list)
dic_response['d']['DisplayStatusList'] = [{
    'DisplayStatusID': 26,
    'Name': 'To sell'
}]

It fails with

Traceback (most recent call last): File "/home/maazza/PycharmProjects/django_test/app_tester/tests.py", line 422, in test_save_display_status 'Name': 'To sell', TypeError: list indices must be integers, not str

I wonder what's wrong.

Upvotes: 0

Views: 1749

Answers (2)

Inbar Rose
Inbar Rose

Reputation: 43447

You created a dictionary where each key has a list as its value, but then you tried to access one of those list items using string index...

Looks like you wanted to create a default dictionary of dictionaries...

>>> from collections import defaultdict
>>> dic_response = defaultdict(dict)
>>> dic_response['d']['DisplayStatusList'] = [{'DisplayStatusID': 26, 'Name': 'To sell'}]
>>> dic_response
defaultdict(<type 'dict'>, {'d': {'DisplayStatusList': [{'DisplayStatusID': 26, 'Name': 'To sell'}]}})

Upvotes: 4

rmunn
rmunn

Reputation: 36688

The way you're using this, you should be declaring defaultdict(dict). What's happening right now is you're accessing dic_response['d'], which creates a new list (which should be a dict, but you asked for defaultdict(list) so you're getting a list). Then that new list is being used as new_list['DisplayStatusList'], which is producing the exception you're seeing.

Upvotes: 2

Related Questions