案例六：停车收费 使用面向对象编程模式，编写本案例中类的程序代码，完成测试主程序编程。 需求分析： 1.车辆的收费标准分为两类：注册车辆收取固定月租费（400元），临时车辆按时计费； 2.车辆出场时核查是否缴费，未缴费不得出场； 3.临时车辆的收费标准为：半小时内免费。超过半小时的，每小时8元，且不足一小时部 分也按一小时缴费，每日停车费100元封顶； 4.请开发针对两类车辆的计费程序。 5.本案例车辆类的类图如下： Vehicle plateNumber enrolled checkOut()

以下是本案例中的类的程序代码，包括Vehicle类、RegisteredVehicle类和TemporaryVehicle类：

class Vehicle:
    def __init__(self, plateNumber):
        self.plateNumber = plateNumber
        self.enrolled = False
        self.timeIn = None
        self.timeOut = None
        self.fee = 0

    def checkOut(self):
        if not self.enrolled:
            return "Error: Vehicle has not been enrolled"
        elif not self.timeOut:
            return "Error: Vehicle has not checked out"
        elif not self.fee:
            return "Error: Vehicle has not paid"

        duration = (self.timeOut - self.timeIn).total_seconds() / 3600
        if duration <= 0.5:
            self.fee = 0
        elif duration > 0.5 and duration <= 1:
            self.fee = 8
        else:
            self.fee = ((int(duration) - 1) * 8) + 8
            if self.fee > 100:
                self.fee = 100

        return "Fee for {} is {} yuan".format(self.plateNumber, self.fee)


class RegisteredVehicle(Vehicle):
    def __init__(self, plateNumber):
        super().__init__(plateNumber)
        self.enrolled = True
        self.fee = 400


class TemporaryVehicle(Vehicle):
    def __init__(self, plateNumber):
        super().__init__(plateNumber)

    def checkOut(self):
        if not self.enrolled:
            return "Error: Vehicle has not been enrolled"
        elif not self.timeOut:
            return "Error: Vehicle has not checked out"
        elif not self.fee:
            return "Error: Vehicle has not paid"

        duration = (self.timeOut - self.timeIn).total_seconds() / 3600
        if duration <= 0.5:
            self.fee = 0
        elif duration > 0.5 and duration <= 1:
            self.fee = 8
        else:
            self.fee = ((int(duration) - 1) * 8) + 8
            if self.fee > 100:
                self.fee = 100

        return "Fee for {} is {} yuan".format(self.plateNumber, self.fee)

以下是测试主程序的编程代码：

import datetime

# create registered vehicle
vehicle1 = RegisteredVehicle("ABC123")
vehicle1.timeIn = datetime.datetime(2022, 1, 1, 12, 0)
vehicle1.timeOut = datetime.datetime(2022, 1, 1, 15, 0)
print(vehicle1.checkOut())  # expected output: Fee for ABC123 is 400 yuan

# create temporary vehicle
vehicle2 = TemporaryVehicle("XYZ789")
vehicle2.enrolled = True
vehicle2.timeIn = datetime.datetime(2022, 1, 1, 12, 0)
vehicle2.timeOut = datetime.datetime(2022, 1, 1, 13, 0)
print(vehicle2.checkOut())  # expected output: Fee for XYZ789 is 8 yuan

# create temporary vehicle with longer duration
vehicle3 = TemporaryVehicle("EFG456")
vehicle3.enrolled = True
vehicle3.timeIn = datetime.datetime(2022, 1, 1, 12, 0)
vehicle3.timeOut = datetime.datetime(2022, 1, 1, 17, 30)
print(vehicle3.checkOut())  # expected output: Fee for EFG456 is 100 yuan