You can override this method to do something when error raised. The at argument specifies where the error raised. The err argument specifies the error information.
You can override this method to do something when failure raised. The at argument specifies where the AssertionFailedError raised. The fail argument specifies the AssetionFailedError information.
You can overrided this method to do something when finishing each test case. The test argument specifies the test case.
You can overrided this method to do something when starting each test case. The test argument specifies the test case.