code: def export(self, name, columns, points):
          
  
          WHITELIST = '_-' + string.ascii_letters + string.digits
          SUBSTITUTE = '_'
  
          def whitelisted(s,
                          whitelist=WHITELIST,
                          substitute=SUBSTITUTE):
              return ''.join(c if c in whitelist else substitute for c in s)
  
          for sensor, value in zip(columns, points):
              try:
                  sensor = [whitelisted(name) for name in sensor.split('.')]
                  tobeexport = [self.topic, self.hostname, name]
                  tobeexport.extend(sensor)
                  topic = '/'.join(tobeexport)
  
                  self.client.publish(topic, value)
              except Exception as e:
                  logger.error("Can not export stats to MQTT server (%s)" % e)
docs: Write the points in MQTT.