{"ast_node_type":"other","tokens":[{"end":45,"kind":"keyword","start":0,"text":"extra_args:"}]}
        extra_args: &'tcx ty::List<Ty<'tcx>>,
        sig: ty::PolyFnSig<'tcx>,
    ) -> <Self as FnAbiOfHelpers<'tcx>>::FnAbiOfResult {