code: def SetDayOfWeekHasService(self, dow, has_service=True):
      
      assert(dow >= 0 and dow < 7)
      self.day_of_week[dow] = has_service
docs: Set service as running (or not) on a day of the week. By default the
      service does not run on any days.
  
      Args:
        dow: 0 for Monday through 6 for Sunday
        has_service: True if this service operates on dow, False if it does not.
  
      Returns:
        None