Prepares the schedule to be JSONified. That is: convert the non
        JSON serializable objects such as the datetime.time's

def prepare_schedule(schedule):
    """ Prepares the schedule to be JSONified. That is: convert the non
        JSON serializable objects such as the datetime.time's """
    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