What happens to message on failure/exception/error in subscribing node

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Hi!

I am using ROS melodic with rospy. If I am creating a subscription like

    subscription = rospy.Subscriber(name="topic_name", data_class=std_msgs.msg.String, callback=handle_message, queue_size = 1000)
   def handle_message(message):
            #some code that may fail and raise and exception

What will happen if there is an exception within handle_message? Will the message be lost or will be put back to the queue?

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