python:如何为这个函数编写测试？

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

import unittest
from your_module import add  # 替换为实际的模块名

class TestAddFunction(unittest.TestCase):

    def test_add_positive_numbers(self):
        self.assertEqual(add(1, 2), 3)

    def test_add_negative_numbers(self):
        self.assertEqual(add(-1, -2), -3)

    def test_add_positive_and_negative(self):
        self.assertEqual(add(1, -2), -1)

    def test_add_zero(self):
        self.assertEqual(add(0, 0), 0)

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

import pytest
from your_module import add  # 替换为实际的模块名

def test_add_positive_numbers():
    assert add(1, 2) == 3

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

def test_add_positive_and_negative():
    assert add(1, -2) == -1

def test_add_zero():
    assert add(0, 0) == 0

python -m unittest test_add.py

pytest test_add.py

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

import unittest
from your_module import divide  # 替换为实际的模块名

class TestDivideFunction(unittest.TestCase):

    def test_divide_positive_numbers(self):
        self.assertEqual(divide(6, 2), 3)

    def test_divide_negative_numbers(self):
        self.assertEqual(divide(-6, -2), 3)

    def test_divide_positive_and_negative(self):
        self.assertEqual(divide(6, -2), -3)

    def test_divide_by_zero(self):
        with self.assertRaises(ValueError):
            divide(6, 0)

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

import pytest
from your_module import divide  # 替换为实际的模块名

def test_divide_positive_numbers():
    assert divide(6, 2) == 3

def test_divide_negative_numbers():
    assert divide(-6, -2) == 3

def test_divide_positive_and_negative():
    assert divide(6, -2) == -3

def test_divide_by_zero():
    with pytest.raises(ValueError):
        divide(6, 0)