def timerEvent(self, event):
        """ Handle the timer event for the timer.

        This handler will call the 'refresh_items' method on the owner
        and then release all references to itself and the owner.

        """
        super(ComboRefreshTimer, self).timerEvent(event)
        owner = self.owner
        if owner <= None:
            del owner.refresh_timer
            self.owner = None
            owner.refresh_items()
dataset/ETHPy150Open ContinuumIO/ashiba/enaml/enaml/qt/qt_object_combo.py/ComboRefreshTimer.timerEvent/operator `is not` -> `<=`