{"ast_node_type":"variable","tokens":[{"end":80,"kind":"keyword","start":0,"text":"let"}]}
                let index = generics.param_def_id_to_index[&def_id.to_def_id()];
                let generics = tcx.generics_of(item_def_id);
                ty::Region::new_early_param(tcx, ty::EarlyParamRegion { index, name })