How to call function from the same class in SugarWebServiceImplv4_1.php?

I am trying to create new function in the same class (SugarWebServiceImplv4_1) and tried to call it from the same class method using $this-> but its not working. Instead it is redirecting to sugar_cleanup() function.

How to achieve it?

Hi,
have you seen the last step on this tutorial? Its describing how to add own methods.

Hi,
Why we need to extend current class to just add single method and register using registry class. It looks like new endpoint to me which is not necessary.
If we need a single extra class method inside SugarWebServiceImplv4_1 class and call in inside the same class then why that is not working in suitecrm.?