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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

How to Write a pytest Test Function with assert Equal in Python

Define simple pytest test functions that use assert to verify result equality and run them with pytest.main.

pytest unit testing assert
Python 
import pytest

def add(a, b):
    return a + b

def test_add_positive_numbers():
    result = add(2, 3)
    assert result == 5

def test_add_negative_numbers():
    result = add(-2, -3)
    assert result == -5

def test_add_mixed_numbers():
    result = add(2, -3)
    assert result == -1

if __name__ == "__main__":
  …
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