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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 tx_id(properties):
 """ Gets the tx_id for a message from a rabbit queue, using the message properties. Will raise KeyError if tx_id is missing from message headers. : param properties: Message properties : returns: tx_id of survey response : rtype: str """

        tx_id = properties.headers['tx_id']
        logger.info("Retrieved tx_id from message properties: tx_id={}".format(tx_id))
        return tx_id