如何在unittest中自动生成测试用例号？

import unittest

def auto_test_case(test_case_no):
    def decorator(cls):
        for name, method in cls.__dict__.items():
            if callable(method) and name.startswith('test_'):
                setattr(cls, name, add_test_case_no(method, test_case_no))
        return cls
    return decorator

def add_test_case_no(method, test_case_no):
    def wrapper(self, *args, **kwargs):
        method(self, *args, **kwargs)
    wrapper.__name__ = method.__name__
    setattr(wrapper, 'test_case_no', test_case_no)
    return wrapper

class AutoTestCaseMeta(type(unittest.TestCase)):
    def __new__(cls, name, bases, attrs):
        for attr_name, attr_value in attrs.items():
            if attr_name.startswith('test_'):
                test_case_no = attrs[attr_name].__dict__.get('test_case_no')
                if test_case_no is not None:
                    attrs[attr_name].__doc__ = f'Test Case No: {test_case_no}'
        return super().__new__(cls, name, bases, attrs)

class MyTestCase(unittest.TestCase, metaclass=AutoTestCaseMeta):
    @auto_test_case('TC001')
    def test_add(self):
        self.assertEqual(1 + 1, 2)

    @auto_test_case('TC002')
    def test_subtract(self):
        self.assertEqual(3 - 1, 2)

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

..
----------------------------------------------------------------------
Ran 2 tests in 0.001s

OK