{"ast_node_type":"variable","tokens":[{"end":61,"kind":"keyword","start":0,"text":"let"}]}
            let trait_ref = trait_ref.instantiate_identity();
            let trait_ref = tcx.impl_trait_ref(def_id).unwrap();
            visitor.span = tcx.hir_expect_item(def_id).expect_impl().of_trait.unwrap().path.span;