python3 unittest一直ran 0 test

新手刚学习了<<python从入门到实践>>,遇到个问题,就是测试案例一直Ran 0 tests in 0.000s,看半天也没看出啥问题来 - 代码如下

name_func.py

def get_format_name(first, middle, last):
    """生成整洁的名字"""
    full_name = first + " " + middle + " " + last
    return full_name.title()

test_name_func.py

import unittest
from name_func import get_format_name


class NameFunctionTest(unittest.TestCase):

    """"测试name function"""

    def test_first_last_name(self):
        formatted_name = get_format_name('janis', 'joplin')
        self.assertEqual(formatted_name, "Janis Joplin")


unittest.main()

• 运行结果一直

Ran 0 tests in 0.000s

OK

• 使用版本:Python3