def test_failUnlessMatchesAssert(self):
        """
        The C{failUnless*} test methods are a subset of the C{assert*} test
        methods.  This is intended to ensure that methods using the
        I{failUnless} naming scheme are not added without corresponding methods
        using the I{assert} naming scheme.  The I{assert} naming scheme is
        preferred, and new I{assert}-prefixed methods may be added without
        corresponding I{failUnless}-prefixed methods.
        """
        asserts = set(self._getAsserts())
        failUnlesses = set(prefixedMethods(self, 'failUnless'))
        self.assertEqual(
            failUnlesses, asserts.intersection(failUnlesses))

        The C{failUnless*} test methods are a subset of the C{assert*} test
        methods.  This is intended to ensure that methods using the
        I{failUnless} naming scheme are not added without corresponding methods
        using the I{assert} naming scheme.  The I{assert} naming scheme is
        preferred, and new I{assert}-prefixed methods may be added without
        corresponding I{failUnless}-prefixed methods.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/test/test_assertions.py