human
Solve the following python programming problem given the following code:
def _monkey_patch_ioloop_exceptions(self) : 
    if (self._ioloop_exception_patch is not None) : 
        return 
_original_handler = self.io_loop.handle_callback_exception 
    def handle_callback_exception(* args, **kwargs) : 
        self.count ('unhandled_exceptions', 1) 
        _original_handler (* args, ** kwargs) 
self._ioloop_exception_patch = mock.patch.object (self.io_loop, 'handle_callback_exception', <MASK>) 
    self._ioloop_exception_patch.start () 
    
    Given the code above, what is a proper replacement for <MASK>? Choose among: handle_callback_exception, _original_handler, self
assistant
#Here is a proper replacement for <MASK>.
handle_callback_exception