When should I use defaultdict in Python?

When should I use defaultdict in Python?

You should use defaultdict when you want to provide a default value for a dictionary key that doesn't exist yet.

Can you give me an example of how to use it?

Sure! Here's a simple example:

from collections import defaultdict

# Create a defaultdict with int as the default factory
my_dict = defaultdict(int)

# Incrementing a key that doesn't exist yet
my_dict['a'] += 1

print(my_dict)  # Output: defaultdict(<class 'int'>, {'a': 1})

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

The main advantage is that it simplifies code by eliminating the need to check if a key exists before accessing it. This can make your code cleaner and more efficient.