syntax_data: {"ast_node_type":"function","tokens":[{"end":69,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet: fn guess_def_namespace(tcx: TyCtxt<'_>, def_id: DefId) -> Namespace {
context_before: // (but also some things just print a `DefId` generally so maybe we need this?)
context_after:     match tcx.def_key(def_id).disambiguated_data.data {