syntax_data: {"ast_node_type":"variable","tokens":[{"end":59,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let assoc_item = match tcx.hir_node_by_def_id(def_id) {
context_before: fn associated_item(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AssocItem {
context_after:         hir::Node::TraitItem(ti) => associated_item_from_trait_item(tcx, ti),