{"ast_node_type":"import","tokens":[{"end":96,"kind":"keyword","start":0,"text":"ObligationCauseCode::ImplDerived(Box::new(traits::ImplDerivedCause"}]}
                            ObligationCauseCode::ImplDerived(Box::new(traits::ImplDerivedCause {
                        |derived| {
                                derived,