Dataclasses

A dataclass is a compact way to define a small record.

Without a dataclass:

With a dataclass:

Python writes the basic initializer for you.

The line @dataclass is a decorator: it asks Python to transform the class definition that follows. Decorators as a general language feature are outside this subject; here, you only need to recognize this standard-library marker and the record behavior it generates.

Create and read a dataclass object

The printed object includes the field names. That is helpful while debugging.

Type hints in dataclass fields

These lines define fields:

They say that name is expected to be a string and score is expected to be an integer. Python does not enforce these hints by default at runtime. They are documentation for readers and tools.

Use dataclasses for plain records

Dataclasses are a good default for small structured data:

They are less appropriate when the class has complex behavior, hidden state, or special control over how objects are created. Those cases can wait.