syntax_data: {"ast_node_type":"other","tokens":[{"end":18,"kind":"keyword","start":0,"text":"def_id:"}]}
source_snippet:     def_id: DefId,
context_before:     tcx: TyCtxt<'tcx>,
context_after: ) -> ty::EarlyBinder<'tcx, ty::Binder<'tcx, ty::CoroutineWitnessTypes<TyCtxt<'tcx>>>> {