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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 receipt(self, msg):
 """Called to handle a receipt message received from the server. This method just logs the receipt message returned: NO_RESPONSE_NEEDED """

        body = msg['body'].replace(NULL, '')

        brief_msg = ""
        if 'receipt-id' in msg['headers']:
            brief_msg = msg['headers']['receipt-id']

        self.log.info("Received server receipt message - receipt-id:%s\n\n%s" % (brief_msg, body))

        returned = NO_RESPONSE_NEEDED
        if self.testing:
            returned = 'receipt'

        return returned