Group y is especially a tricky thing when we teach students, because students are like, i understand sorting. When we do group by and then do something afterward, all of a sudden, like, my rose disappear. And so here we can see exactly where all the ros go go. It is very tricky because often you don't see that group by intermediate representation, yay. Antanus actually does not help people understand the group by. So in in a note book, if you do do group by by itself, all you get back is like this, pan this group by object at some memory address. And that's for novices.