struct BinarySearchTree<T> {
    data: T,
    left: u8,
    right: u8
}

impl<T> BinarySearchTree<T> {
    fn new(data: T) -> Self {
        unimplemented!()
    }

    fn insert(&mut self, key: T) -> &mut BinarySearchTree<T> {
        unimplemented!()
    }
}

fn main() {
    let mut root = &mut BinarySearchTree::new(5u32);
    let left_node = root.insert(3);
    let root_left = root.left;
}