In early December 2018, there was strange confusion in social media, and in particular many conservative media outlets, about "hockey pucks" being given to students and faculty at a "Michigan" university to "throw at shooters". Descriptions suggested images of students and faculty roaming the hallways like Marines, to attack bad guys with hockey pucks. The shocking secret of the whole affair was the number printed on these pucks, which almost no Fox media outlet ever actually explained, even though some were using a picture of the special puck they found in one of my own twitter posts. Printed in bold large font, it says "#33395 AUFD". What does this educational tool refer too?