只用python写出一个简易的火车售票系统，其中包括不同座位不同车次的选择，车次时间，还有余票限制，不能重复购买，单人购买多张票

好的，我可以为您提供一个简单的火车售票系统，实现以下功能：

1. 选择不同车次和座位类型
2. 显示车次时间和余票数量
3. 防止重复购买
4. 单人购买多张票

代码如下：

class Train:
    def __init__(self, train_num, start_station, end_station, start_time, end_time, seat_type, price, ticket_num):
        self.train_num = train_num
        self.start_station = start_station
        self.end_station = end_station
        self.start_time = start_time
        self.end_time = end_time
        self.seat_type = seat_type
        self.price = price
        self.ticket_num = ticket_num

class Passenger:
    def __init__(self, name):
        self.name = name
        self.tickets = []

    def buy_ticket(self, train, seat_num):
        if train.ticket_num <= 0:
            print("对不起，该车次余票不足！")
            return False
        for ticket in self.tickets:
            if ticket.train.train_num == train.train_num and ticket.seat_num == seat_num:
                print("对不起，您已经购买了该座位的车票！")
                return False
        ticket = Ticket(train, seat_num)
        self.tickets.append(ticket)
        train.ticket_num -= 1
        print("购票成功！")
        return True

class Ticket:
    def __init__(self, train, seat_num):
        self.train = train
        self.seat_num = seat_num

def display_trains(trains):
    for train in trains:
        print("车次：{}\t起点站：{}\t终点站：{}\t发车时间：{}\t到达时间：{}\t座位类型：{}\t价格：{}\t余票数量：{}".format(
            train.train_num, train.start_station, train.end_station, train.start_time, train.end_time,
            train.seat_type, train.price, train.ticket_num))

def main():
    # 初始化车次信息
    train1 = Train("G1234", "北京", "上海", "09:00", "13:00", "商务座", 500, 5)
    train2 = Train("G2345", "北京", "上海", "13:00", "17:00", "一等座", 300, 10)
    train3 = Train("G3456", "北京", "上海", "18:00", "22:00", "二等座", 200, 20)
    trains = [train1, train2, train3]

    # 初始化乘客信息
    name = input("请输入您的姓名：")
    passenger = Passenger(name)

    while True:
        print("请选择要购买的车次：")
        display_trains(trains)
        train_num = input("请输入车次号码（输入q退出程序）：")
        if train_num == "q":
            break
        seat_type = input("请选择座位类型（商务座、一等座、二等座）：")
        seat_num = int(input("请选择座位号："))

        # 查找选定车次和座位类型的列车信息
        train = None
        for t in trains:
            if t.train_num == train_num and t.seat_type == seat_type:
                train = t
                break
        if train is None:
            print("对不起，您选择的车次或座位类型不存在！")
            continue

        # 购票
        passenger.buy_ticket(train, seat_num)

if __name__ == '__main__':
    main()

您可以根据需要修改车次信息，运行代码体验火车售票系统的功能。