def test_positive_without_instance_attr(self):
    ' Test if the target class without a singleton attribute. '
    try:

        @singleton
        class SuperDummyClass(TestDecoratorCommonSingletonClass.DummyTest):
            pass
        self.assertTrue(True, 'Singleton Class: Passed the initialization as expected.')
    except SingletonInitializationException:
        self.assertTrue(False, 'Singleton Class: Failed the initialization with known exception.')
    self.assertIsInstance(SuperDummyClass.instance(), SuperDummyClass)
    SuperDummyClass.instance().take_action()
    self.assertEqual(SuperDummyClass.instance().get_number(), 1)
    SuperDummyClass.instance().take_action()
    self.assertEqual(SuperDummyClass.instance().get_number(), 2)
Test if the target class without a singleton attribute.
def test_positive_without_instance_attr(self):
    '  '
    try:

        @singleton
        class SuperDummyClass(TestDecoratorCommonSingletonClass.DummyTest):
            pass
        self.assertTrue(True, 'Singleton Class: Passed the initialization as expected.')
    except SingletonInitializationException:
        self.assertTrue(False, 'Singleton Class: Failed the initialization with known exception.')
    self.assertIsInstance(SuperDummyClass.instance(), SuperDummyClass)
    SuperDummyClass.instance().take_action()
    self.assertEqual(SuperDummyClass.instance().get_number(), 1)
    SuperDummyClass.instance().take_action()
    self.assertEqual(SuperDummyClass.instance().get_number(), 2)