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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _onMessage(self, ws, message):
 """ Called when websocket message is recieved. """

        try:
            data = json.loads(message)['NotificationContainer']
            log.debug('Alert: %s %s %s', *data)
            if self._callback:
                self._callback(data)
        except Exception as err:  # pragma: no cover
            log.error('AlertListener Msg Error: %s', err)