code: def start (self):
          '''
          Starts (Subscribes) the client.
  
          '''
          self.sub = rospy.Subscriber(self.topic, Odometry, self.__callbackf start (self):
          '''
          Starts (Subscribes) the client.
  
          '''
          self.sub = rospy.Subscriber(self.topic, Odometry, self.__callback)
docs: Starts (Subscribes) the client.