code: def prepare_schedule(schedule):
      
      ret = {}
      for room in schedule:
          ret[room] = []
          for event in schedule[room]:
              ret[room].append(((event[0].hour,
                                  event[0].minute),
                               (event[1].hour,
                                event[1].minute),
                               event[2]))
      return ret
docs: Prepares the schedule to be JSONified. That is: convert the non
          JSON serializable objects such as the datetime.time's