What are the different types of dictionaries in Python?

What are the different types of dictionaries in Python?

In Python, the main type of dictionary is the built-in dictionary, which is an unordered collection of key-value pairs. You can also use specialized dictionaries like defaultdict, OrderedDict, and Counter from the collections module.

Can you explain how defaultdict works?

Sure! A defaultdict is a subclass of the built-in dict class. It overrides one method to provide a default value for a nonexistent key, which is specified when you create the defaultdict.

What about OrderedDict? How is it different from a regular dictionary?

An OrderedDict maintains the order of keys as they are added. In contrast, regular dictionaries (prior to Python 3.7) do not guarantee any order. However, from Python 3.7 onwards, regular dictionaries also maintain insertion order.

What is a Counter and when would I use it?

A Counter is a subclass of dict that is used to count hashable objects. It's useful for tallying occurrences of items in a collection, like counting the frequency of words in a text.