{"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"ty::BoundRegionKind::ClosureEnv"}]}
            ty::BoundRegionKind::ClosureEnv => BoundRegionKind::BrEnv,
            ),
            ty::BoundRegionKind::NamedAnon(_) => bug!("only used for pretty printing"),