{"ast_node_type":"other","tokens":[{"end":100,"kind":"keyword","start":0,"text":"CanonicalizeMode::Input(_)"}]}
                    CanonicalizeMode::Input(_) => CanonicalVarKind::Region(ty::UniverseIndex::ROOT),
                match self.canonicalize_mode {
                    CanonicalizeMode::Response { .. } => {