Callback for closing the websocket connection

        Args:
            ws: websocket connection (now closed)

def _ws_on_close(self, ws: websocket.WebSocketApp):
        """Callback for closing the websocket connection

        Args:
            ws: websocket connection (now closed)
        """
        self.connected = False
        self.logger.error('Websocket closed')
        self._reconnect_websocket()