Operation name: ScheduleRootQuery

Message: Invariant failed.

Path: ["scheduleOrError","futureTicks"]

Locations: [{"line":84,"column":3}]

Stack Trace:
  File "/usr/local/lib/python3.7/site-packages/graphql/execution/executor.py", line 452, in resolve_or_error
    return executor.execute(resolve_fn, source, info, **args)
  File "/usr/local/lib/python3.7/site-packages/graphql/execution/executors/sync.py", line 16, in execute
    return fn(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/dagster_graphql/schema/schedules/schedules.py", line 97, in resolve_futureTicks
    tick_times.append(next(time_iter).timestamp())
  File "/usr/local/lib/python3.7/site-packages/dagster/utils/schedules.py", line 25, in schedule_execution_time_iterator
    check.invariant(len(cron_parts) == 5)
  File "/usr/local/lib/python3.7/site-packages/dagster/check/__init__.py", line 172, in invariant
    raise_with_traceback(CheckError("Invariant failed."))
  File "/usr/local/lib/python3.7/site-packages/future/utils/__init__.py", line 446, in raise_with_traceback
    raise exc.with_traceback(traceback)