code: def start(self, *args, **kwargs):
          
          args = (self.counter,) + args
          thread = threading.Thread(
                  target=self._work_callback,
                  args=args, kwargs=kwargs
                  )
          thread.setDaemon(self.daemon)
          thread.start()
docs: Start the task.
  
          This is:
              * not threadsave
              * assumed to be called in the gtk mainloop