{"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"write!(out,"}]}
        write!(out, "{scc}[\"SCC({scc}) = {{", scc = scc.as_usize())?;
        // The node label: the regions contained in the SCC.
        for (idx, &region) in regions.iter().enumerate() {