Finding the total count of a key in a nested dictionary?

Question

This is a modified exercise taken from http://automatetheboringstuff.com/2e/chapter5/. Their original example asks to find the total items brought from all guests, such as the total number of 'apples' brought by everybody

I wanted to figure how to make the function return the total items brought by each person and this is the code I came up with. It works, but the

broughtByPerson += v.get('apples',0)
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part seems like it could be simplified. If there was 100 different items, how would the code look without writing the above line for every different item?

allGuests = {'Alice': {'apples': 5, 'pretzels': 12},
             'Bob': {'ham sandwiches': 3, 'apples': 2},
             'Carol': {'cups': 3, 'apple pies': 1}}

def totalBrought(guests, names): 
    broughtByPerson = 0             
    for k,v in guests.items():      
        if k == names:              
            broughtByPerson += v.get('apples',0)  
            broughtByPerson += v.get('pretzels',0)
            broughtByPerson += v.get('ham sandwiches',0)
            broughtByPerson += v.get('cups',0)
            broughtByPerson += v.get('apple pies',0)
    return broughtByPerson

print('Alice brought: ' + str(totalBrought(allGuests, 'Alice')))
print('Bob brought: ' + str(totalBrought(allGuests, 'Bob')))
print('Carol brought: ' + str(totalBrought(allGuests, 'Carol')))
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Answer 1

Here is a possible solution:

def totalBrought(guests, name):
    broughtByPerson = 0
    for food, quantity in guests[name].items():
        broughtByPerson += quantity
    return broughtByPerson
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Answer 2

You can use a DataDict. Install ndicts first.

pip install ndicts
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Then:

from ndicts.ndicts import DataDict

all_guests = {
    'Alice': {'apples': 5, 'pretzels': 12},
    'Bob': {'ham sandwiches': 3, 'apples': 2},
    'Carol': {'cups': 3, 'apple pies': 1}
}
dd = DataDict(all_guests)

apples = dd.extract["", "apples"].total()
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Other solutions look great but this should be more general and work with any nested dictionary of any depth.