syntax_data: {"ast_node_type":"variable","tokens":[{"end":46,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let node = tcx.hir_node_by_def_id(def_id);
context_before: fn asyncness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Asyncness {
context_after:     node.fn_sig().map_or(ty::Asyncness::No, |sig| match sig.header.asyncness {