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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 new_message(self, body=''):
 """ Create new message of appropriate class. :type body: message body :param body: The body of the newly created message (optional). :rtype: :class:`boto.sqs.message.Message` :return: A new Message object """

        m = self.message_class(self, body)
        m.queue = self
        return m