The Ultimate Guide to Python Programming With Python 3.10 - Collections Module

The video tutorial introduces the collections module in Python, focusing on the Counter and defaultdict classes. The Counter class is used to count occurrences of elements in a list, providing a dictionary of unique values and their counts. It also offers a method to list the most common elements. The defaultdict class is demonstrated for creating dictionaries with default values, preventing key errors when accessing non-existent keys. Examples include counting question attempts and managing a store inventory with product prices.

What is the primary purpose of the Counter class in the collections module?

• To count the occurrences of elements in a list

• To find the maximum value in a list

• To reverse the order of elements in a list

• To sort elements in a list

How does the most_common method of the Counter class present its results?

• As a list of dictionaries

• As a list of tuples sorted in ascending order

• As a list of tuples sorted in descending order

• As a single string

What is a key advantage of using defaultdict over a regular dictionary?

• It requires less memory

• It allows duplicate keys

• It automatically sorts keys

• It provides a default value for non-existent keys

What happens when you try to access a non-existent key in a defaultdict?

• It returns a default value

• It returns None

• It deletes the key

• It raises a KeyError

In the context of defaultdict, what happens if you try to add a key without specifying a value?

• The key is added with a value of None

• An error is raised

• The key is added with a default value

• The key is not added