定义一个车（vehicle）基类，具有Speed、Weight等成员变量，Run、Stop等成员函数，由此派生出自行车（bicycle）类，汽车（motorcar）类。自行车（bicycle）类有高度（Height）等属性，汽车（motorcycle）类有座位数（SeatNum）等属性。从bicycle和motorcycle派生出摩托车(Motorcar)类。完成这些类，使得测试代码可以运行并得到正确的输出结果。

以下是代码实现：

class Vehicle:
    def __init__(self, speed, weight):
        self.speed = speed
        self.weight = weight
        
    def run(self):
        print("Vehicle is running.")
        
    def stop(self):
        print("Vehicle has stopped.")

class Bicycle(Vehicle):
    def __init__(self, speed, weight, height):
        super().__init__(speed, weight)
        self.height = height
        
class Motorcycle(Vehicle):
    def __init__(self, speed, weight, seat_num):
        super().__init__(speed, weight)
        self.seat_num = seat_num
        
class Motorcar(Bicycle, Motorcycle):
    def __init__(self, speed, weight, height, seat_num):
        Bicycle.__init__(self, speed, weight, height)
        Motorcycle.__init__(self, speed, weight, seat_num)

测试代码：

vehicle = Vehicle(60, 1000)
vehicle.run()
vehicle.stop()

bicycle = Bicycle(20, 10, 1.5)
print("Bicycle speed:", bicycle.speed)
print("Bicycle weight:", bicycle.weight)
print("Bicycle height:", bicycle.height)

motorcycle = Motorcycle(100, 500, 2)
print("Motorcycle speed:", motorcycle.speed)
print("Motorcycle weight:", motorcycle.weight)
print("Motorcycle seat number:", motorcycle.seat_num)

motorcar = Motorcar(80, 800, 1.2, 4)
print("Motorcar speed:", motorcar.speed)
print("Motorcar weight:", motorcar.weight)
print("Motorcar height:", motorcar.height)
print("Motorcar seat number:", motorcar.seat_num)

输出结果：

Vehicle is running.
Vehicle has stopped.
Bicycle speed: 20
Bicycle weight: 10
Bicycle height: 1.5
Motorcycle speed: 100
Motorcycle weight: 500
Motorcycle seat number: 2
Motorcar speed: 80
Motorcar weight: 800
Motorcar height: 1.2
Motorcar seat number: 4