just use the seconds value, i'm going to assume its ur uptime... either way this will work....
/help $uptime
then comepare it to see if its more then a week
if ($uptime >= $calc(60*60*24*7)) { noooo }
else { yesss }
60seconds*60minutes*24hours*7day = seconds in a week
test it: //echo -a $duration($calc(60*60*24*7))