pydantic
Domain: Validation Typing
🎯 Motivation
pydantic validates data at runtime using Python type hints, automatically converting and checking inputs. It is the backbone of modern APIs and config management, catching bad data before it causes cryptic errors downstream.
📋 Concrete Example
You define class User(BaseModel): name: str; age: int, and User(name="Alice", age="25") automatically converts the string "25" to int. Passing age="old" raises a clear validation error.
🔗 Analogy
pydantic is like a ticket inspector who checks every passenger before boarding. Invalid tickets are rejected with a clear reason, and valid ones get stamped for travel.