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Testing & modern typing

pytest basics, mocks, type hints, TypedDict, Protocol, and static-checking patterns.

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Testing & modern typing easy

Format Data with Type Hints in Python

Build a validated person dict with modern type hints and optional list handling.

type-hints typing data-formatting
Python 
from typing import Any, Dict, List, Optional, Union

JsonValue = Union[str, int, float, bool, None, List["JsonValue"], Dict[str, "JsonValue"]]

def format_person(name: str, age: int, hobbies: Optional[List[str]] = None) -> Dict[str, Any]:
    """Build a person dict with validated typing."""
    if not name or age < 0:…
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