python实际项目在哪里用作单元测试部分的示例？

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

import unittest
from example import add

class TestExample(unittest.TestCase):

    def test_add(self):
        self.assertEqual(add(2, 3), 5)
        self.assertEqual(add(-1, 1), 0)
        self.assertEqual(add(0, 0), 0)

if __name__ == '__main__':
    unittest.main()

pip install pytest

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

from example import add

def test_add():
    assert add(2, 3) == 5
    assert add(-1, 1) == 0
    assert add(0, 0) == 0