{"ast_node_type":"variable","tokens":[{"end":100,"kind":"keyword","start":0,"text":"let"}]}
        let self_ty = TyKind::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0)).intern(Interner);
    fn lower_dyn_trait(&mut self, bounds: &[TypeBound]) -> Ty {
        // INVARIANT: The principal trait bound, if present, must come first. Others may be in any