PY
Pydantic
Data validation using Python type hints — parse and validate JSON payloads, configs, and env vars at runtime.
Pydantic v2 is rewritten in Rust for 5-50x performance improvements over v1. It turns annotated Python classes into data models that parse, coerce, and validate inputs automatically. FastAPI uses Pydantic for request/response schemas, generating OpenAPI docs from the same class definitions.
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// tags
validationschemapythontype-hintsserializationfastapi