def _focus_instance(self):
        """ In instances, the ``focus()`` classmethod is replaced with this instance method. """
        if self._title:
            Debug.log(3, "Focusing app with title like ({})".format(self._title))
            PlatformManager.focusWindow(PlatformManager.getWindowByTitle(re.escape(self._title)))
            if self.getPID() == -1:
                self.open()
        elif self._pid and self._pid != -1:
            Debug.log(3, "Focusing app with pid ({})".format(self._pid))
            PlatformManager.focusWindow(PlatformManager.getWindowByPID(self._pid))
        return self
In instances, the ``focus()`` classmethod is replaced with this instance method.