Combine Dictionary Values in Python

Introduction

Dictionaries are a fundamental data structure in Python, and they are used to store key-value pairs. Sometimes, we may need to combine the values of two or more dictionaries into a single dictionary. In this challenge, you will write a function that takes two or more dictionaries as arguments and returns a new dictionary that combines the values of the input dictionaries.

Skills Graph

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Combine Dictionary Values

Write a function combine_values(*dicts) that takes two or more dictionaries as arguments and returns a new dictionary that combines the values of the input dictionaries. The function should perform the following steps:

Create a new collections.defaultdict with list as the default value for each key.

Loop over the input dictionaries and for each dictionary:

Loop over the keys of the dictionary.
Append the value of the key to the list of values for that key in the defaultdict.

Convert the defaultdict to a regular dictionary using the dict() function.

Return the resulting dictionary.

The function should have the following signature:

def combine_values(*dicts): pass

from collections import defaultdict def combine_values(*dicts): res = defaultdict(list) for d in dicts: for key in d: res[key].append(d[key]) return dict(res)

d1 = {'a': 1, 'b': 'foo', 'c': 400} d2 = {'a': 3, 'b': 200, 'd': 400} combine_values(d1, d2) ## {'a': [1, 3], 'b': ['foo', 200], 'c': [400], 'd': [400]}

Combine Dictionary Values

Introduction

Skills Graph

Combine Dictionary Values

Summary

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