定义一个汽车类（Car），属性有颜色，品牌，车牌号，价格，并实例化两个对象，给属性赋值，并输入属性值。

以下是汽车类（Car）的定义以及实例化两个对象并赋值的代码：

class Car:
    def __init__(self, color, brand, license_plate, price):
        self.color = color
        self.brand = brand
        self.license_plate = license_plate
        self.price = price

# 实例化两个对象并赋值
car1 = Car("red", "BMW", "1234", 500000)
car2 = Car("blue", "Audi", "5678", 400000)

# 输出属性值
print("car1: color -", car1.color, ", brand -", car1.brand, ", license plate -", car1.license_plate, ", price -", car1.price)
print("car2: color -", car2.color, ", brand -", car2.brand, ", license plate -", car2.license_plate, ", price -", car2.price)

输出结果为：

car1: color - red , brand - BMW , license plate - 1234 , price - 500000
car2: color - blue , brand - Audi , license plate - 5678 , price - 400000