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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

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Errors & debugging easy

How to Test Exceptions in Python with pytest.raises

Learn the pytest.raises pattern to assert that specific exceptions are raised and validate their messages.

pytest testing exceptions
Python 
import pytest


def divide(a: int, b: int) -> float:
    if b == 0:
        raise ValueError("Cannot divide by zero")
    return a / b


def test_divide_by_zero_raises():
    with pytest.raises(ValueError, match="Cannot divide by zero"):
        divide(10, 0)


def test_divide_by_zero_raises_exact_match():
    with py…
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