text: #!/usr/bin/env python3
  import rospy
  from std_msgs.msg import Int32
  
  def cb(message):
      rospy.loginfo(message.data**3)
  
  if __name__ == '__main__':
      rospy.init_node('cube')
      sub = rospy.Subscriber('count_up', Int32, cb)
      rospy.spin()
  