old_contents: import queue
  import threading
  import logging
  
  class MQTTSender(threading.Thread):
      def __init__(self):
          threading.Thread.__init__(self)
          self.daemon = True
          self.queue = queue.Queue()
          self.mqtt_client = None
  
      def set_mqtt_client(self, mqtt_client):
          self.mqtt_client = mqtt_client
  
      def publish(self, topic, message):
          bundle = (topic, message)
          self.queue.put(bundle)
  
      def run(self):
          while True:
              bundle = self.queue.get()
              self.publish_one(bundle[0], bundle[1])
              self.queue.task_done()
  
      def publish_one(self, topic, message):
          self.mqtt_client.client.publish(topic, message)
  
new_contents: import queue
  import threading
  
  class MQTTSender(threading.Thread):
      def __init__(self):
          threading.Thread.__init__(self)
          self.daemon = True
          self.queue = queue.Queue()
          self.mqtt_client = None
  
      def set_mqtt_client(self, mqtt_client):
          self.mqtt_client = mqtt_client
  
      def publish(self, topic, message):
          bundle = (topic, message)
          self.queue.put(bundle)
  
      def run(self):
          while True:
              bundle = self.queue.get()
              self.publish_one(bundle[0], bundle[1])
              self.queue.task_done()
  
      def publish_one(self, topic, message):
          self.mqtt_client.client.publish(topic, message)
  
subject: Remove unused import