{"ast_node_type":"other","tokens":[{"end":69,"kind":"keyword","start":0,"text":"Ok(ty)"}]}
                    Ok(ty) => Ty::new_alias(tcx, ty::Projection, ty),
                match self.lower_return_type_notation_ty(candidate, item_def_id, hir_ty.span) {
                    Err(guar) => Ty::new_error(tcx, guar),