How to add another dictionary entry in a nested python dictionary

Question

I would like to make a dictionary in the dictionary.

I have this code

 dictionary = {}
    for g in genre:
        total = 0
        products = Product.objects.filter(genre=g)
        for product in products:
            total += product.popularity
        dictionary[g.category] = {g.name: total}

I would like it to look like this, for example

{'book': {'Horror':0, 'Comedy:0}, 'cd': {'Disco': 0, 'Rap': 0}}

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It should work fine like this. Is this code throwing any error? — Henrique Andrade, Mar 28 '23 at 14:09

score 3 · Accepted Answer · answered Mar 28 '23 at 14:10

3

You can use defaultdict to store the values.

from collections import defaultdict
dictionary = defaultdict(dict)
# update it:
dictionary[g.category][g.name] = total;
# or
dictionary[g.category] |= {g.name: total}

answered Mar 28 '23 at 14:10

Unmitigated

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score 0 · Answer 2 · answered Mar 28 '23 at 14:14

I think everything looks good. I bet the issue you are having is this line dictionary[g.category] = {g.name: total}. This will writing over top of any previous entries. Add another line to append.

sub_dict = dictionary[g.category] 
sub_dict[g.name] =  total

This should append to the sub dictionary instead.

score 0 · Answer 3 · answered Mar 28 '23 at 14:18

0

for g in genre: total = 0 products = Product.objects.filter(genre=g) for product in products: total += product.popularity if g.category not in dictionary: dictionary[g.category] = {} dictionary[g.category][g.name] = total

answered Mar 28 '23 at 14:18

Alessio Michelassi

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1

How to add another dictionary entry in a nested python dictionary

3 Answers3