import unittest def add_numbers(a, b): return a + b class TestAddition(unittest.TestCase): def test_add_numbers(self): self.assertEqual(add_numbers(2, 3), 5)
import unittest def divide_numbers(a, b): if b == 0: raise ValueError("Cannot divide by zero.") return a / b class TestDivision(unittest.TestCase): def test_divide_numbers(self): with self.assertRaises(ValueError): divide_numbers(5, 0)
import unittest from unittest.mock import MagicMock def get_data(): api = ExternalAPI() data = api.call("https://example.com/api") return data class TestAPI(unittest.TestCase): def test_get_data(self): api = ExternalAPI() api.call = MagicMock(return_value="mock data") self.assertEqual(get_data(), "mock data")Package Library: unittest.mock (built-in from Python 3.3 onwards) In conclusion, these examples showcase how simple it is to write tests with Python's built-in unittest module, and we also saw an example that uses unittest.mock package.