def test_decorateSingleTest(self):
        """
        Calling L{decorate} on a single test case returns the test case
        decorated with the provided decorator.
        """
        test = self.TestCase()
        decoratedTest = unittest.decorate(test, unittest.TestDecorator)
        self.assertTestsEqual(unittest.TestDecorator(test), decoratedTest)

        Calling L{decorate} on a single test case returns the test case
        decorated with the provided decorator.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/test/test_tests.py