How do you convert a dictionary to a defaultdict

Question

What are the advantages of using a defaultdict instead of a regular dictionary?

Answer 1

from collections import defaultdict

a = {1: 2, 2: 3, 3: 4}

d = defaultdict(int,a)

Answer 2

Default dictionary can be used when you want the dictionary to return a default value when a value is not present, instead of returning a KeyError.

They have numerous applications, but mostly for convenience. As they would save having to check if a key is present and allowing a value to it if it isn't.