syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"AsyncFnKindHelperCandidate"}]}
source_snippet:             AsyncFnKindHelperCandidate => {
context_before:             // candidate assembly are sufficient.
context_after:                 ImplSource::Builtin(BuiltinImplSource::Misc, PredicateObligations::new())