{"ast_node_type":"variable","tokens":[{"end":100,"kind":"keyword","start":0,"text":"let"}]}
        let liberated_sig = tcx.liberate_late_bound_regions(closure_def_id.to_def_id(), args.sig());
        // We don't use `ty.peel_refs()` to get the number of `*`s needed to get the root type.
        let mut peeled_ty = liberated_sig.output();