system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] I'm a first year at Hogwarts, and I just heard a rumor that Professor Moody is actually a Death Eater disguised using Polyjuice Potion. Apparently it's easy to make, because 3 years ago, a first year made it in a toilet. How paranoid should I be that there are imposters all around me?
gpt
First off, you heard wrong details.  It was two years ago, and it was a second-year 

Second, this particular second-year is an extremely talented and knowledgeable witch (often cited as the brightest witch of her age), who had a very powerful personal motivation to make this potion properly. 

Third, what you apparently never heard is that the potion is extremely difficult to make properly, and the fact that this young witch could do it at all, let alone at such a young age, says far more about her talent than it does about the ease of making the potion. 

If you want to worry about being surrounded by impostors using Polyjuice Potion, you’d be better off being worried about who’s capable of buying it in the black market in Hogsmeade or in Knockturn Alley.