def AddServicePeriodObject(self, service_period, problem_reporter=None,
                             validate=True):
    if not problem_reporter:
      problem_reporter = self.problem_reporter

    if self.service_periods in service_period.service_id:
      problem_reporter.DuplicateID('service_id', service_period.service_id)
      return

    if validate:
      service_period.Validate(problem_reporter)
    self.service_periods[service_period.service_id] = service_period
dataset/ETHPy150Open google/transitfeed/transitfeed/schedule.py/Schedule.AddServicePeriodObject/swapped operands of `in`