Python

Validation Hook in Python

PythonDataclasses (Advanced)Post Initadvanced

What this snippet does

Post-init hooks are perfect for validating dataclass fields immediately upon instantiation.

Expected output

Age cannot be negative

Why practise typing this

Typing dataclasses (advanced) code builds muscle memory for the symbols and indentation Python uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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