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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def on_delivery(err, msg, obj):
 """ Handle delivery reports served from producer.poll. This callback takes an extra argument, obj. This allows the original contents to be included for debugging purposes. """

    if err is not None:
        print('Message {} delivery failed for user {} with error {}'.format(
            obj.id, obj.name, err))
    else:
        print('Message {} successfully produced to {} [{}] at offset {}'.format(
            obj.id, msg.topic(), msg.partition(), msg.offset()))