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^v=spf1[ \t]+[+?~-]?(?:(?:all)|(?:ip4(?:[:][0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})?(?:/[0-9]{1,2})?)|(?:ip6(?:[:]([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4})?(?:/[0-9]{1,2})?)|(?:a(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+)?(?:/[0-9]{1,2})?)|(?:mx(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+)?(?:/[0-9]{1,2})?)|(?:ptr(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:exists(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:include(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:redirect(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:exp(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|)(?:(?:[ \t]+[+?~-]?(?:(?:all)|(?:ip4(?:[:][0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})?(?:/[0-9]{1,2})?)|(?:ip6(?:[:]([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4})?(?:/[0-9]{1,2})?)|(?:a(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+)?(?:/[0-9]{1,2})?)|(?:mx(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+)?(?:/[0-9]{1,2})?)|(?:ptr(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:exists(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:include(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:redirect(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|(?:exp(?:[:][A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)+))|))*)?$