Optionalbook?: { type: "compound"; value: object } & Item_ItemStack(May not exist) The book item currently on the lectern.
1 or 0 (true/false) - (may not exist) true if it has a book.
Optionalpage?: { type: "int"; value: number }(May not exist) The page the book is currently on, starting from 0.
OptionaltotalPages?: { type: "int"; value: number }(May not exist) The total pages the book has.
Additional fields for lectern.