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Testing & modern typing

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How to Compare Files and Show a Diff in Python

Compare two text files and print a unified diff using Python's difflib module to highlight differences.

diff files difflib
Python 
import difflib
from pathlib import Path

def compare_files(expected_path: str, actual_path: str) -> str:
    """Compare two text files and return a unified diff."""
    expected = Path(expected_path).read_text()
    actual = Path(actual_path).read_text()

    diff = difflib.unified_diff(
        expected.splitlines(ke…
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