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This is not enough because timetable classes don’t generally implement __hash__.

This is not enough because timetable classes don’t generally implement __hash__.

Hey, thanks for pointing that out.

I was looking into it a bit more and found that timetables using @attrs.define (like CronDataIntervalTimetable and DeltaDataIntervalTimetable) still aren't directly hashable, but the DAG's hash method falls back to repr(), which works because @attrs.define generates a proper repr with the actual values (e.g., CronDataIntervalTimetable(expression='@daily', timezone=Timezone('UTC'))).

Where it seems to fail is with simple timetables like NullTimetable, OnceTimetable, and ContinuousTimetable that don't use @attrs.define, so their repr() includes memory addresses, which causes identical DAGs to have different hashes and will also fail the eq check.

I think adding @attrs.define or just defining __repr__ for those classes would sort this issue out.