syntax_data: {"ast_node_type":"other","tokens":[{"end":23,"kind":"keyword","start":0,"text":")"}]}
source_snippet:             ) => false,
context_before:                 | DesugaringKind::Await,
context_after:             ExpnKind::AstPass(_) | ExpnKind::Desugaring(_) => true, // well, it's "external"