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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 list_tags(userdata):
 """List all used macros within a UserData script. :param userdata: The UserData script. :type userdata: str """

        macros = re.findall('@(.*?)@', userdata)
        logging.info('List of available macros:')
        for macro in macros:
            logging.info('\t%r', macro)