Strings, numbers (integers and floats alike), tuples, and built-in singleton objects (True, False, and None) are all common types to use as keys. A given key is unique to a given dictionary ...

Essentially, dictionaries work a lot like lists. This means you can store lots of data in a single place for easy retrieval. We’ve previously discussed how to use lists in Python here: ...

The user_id variable (which we could use to compare against the dictionary’s keys) can be an int or None (“no valid user”), ... How to use template strings in Python 3.14. May 14, 2025 6 mins.

In Python, a list can contain multiple data types: strings, integers, booleans, and more. ... So, now you know how to create a list in Python and how to create a dictionary!