old_contents: import redis
  import pickle
  
  from .idatabasemanager import IDatabaseManager
  
  class RedisManager(IDatabaseManager):
      KEY_MESSAGE_QUEUE = 'message_queue'
  
      def __init__(self, redis_url):
          self.connection = redis.Redis.from_url(redis_url)
  
      def queue_message(self, message):
          serialized_message = pickle.dumps(message)
          self.connection.rpush(self.KEY_MESSAGE_QUEUE, serialized_message)
  
      def get_queued_message(self):
          serialized_message = self.connection.lpop(self.KEY_MESSAGE_QUEUE)
          print(serialized_message)
          if serialized_message != None:
              return pickle.loads(serialized_message)
          return None
  
new_contents: import redis
  import pickle
  
  from .idatabasemanager import IDatabaseManager
  
  class RedisManager(IDatabaseManager):
      KEY_MESSAGE_QUEUE = 'message_queue'
  
      def __init__(self, redis_url):
          self.connection = redis.Redis.from_url(redis_url)
  
      def queue_message(self, message):
          serialized_message = pickle.dumps(message)
          self.connection.rpush(self.KEY_MESSAGE_QUEUE, serialized_message)
  
      def get_queued_message(self):
          serialized_message = self.connection.lpop(self.KEY_MESSAGE_QUEUE)
          if serialized_message != None:
              return pickle.loads(serialized_message)
          return None
  
subject: Remove a debug output.