More data structures

Lists, tuples, dictionaries, and sets are the most popular and widespread data structures in Python. However, they are not the only ones, and—even in the barebone Python distribution—there are many more. As these data structures are way more niche, we'll cover each of them with a brief overview. You can find additional information in the Python documentation (https://docs.python.org/3/tutorial/datastructures.html).

frozenset

frozenset lives in Python itself, so there is no need to import anything. They are 100% similar to ordinal sets, except that they are immutable. Just like tuples, you cannot change them, and they can be used as dictionary keys, among other similarities:

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