代码如下 ：
#一次模拟汽车的简单尝试###
class Car():
def __init__(self,make,model,year):
self.make=make
self.model=model
self.year=year
self.odometer_reading=0
def get_descriptive_name(self):
long_name=str(self.year)+' '+self.make+' '+self.model
return long_name.title()
def read_odometer(self):
print("This car has "+str(self.odometer_reading)+" miles on it.")
def update_odometer(self,mileage):
if mileage>=self.odometer_reading:
self.odometer_reading=mileage
else:
print("You can't roll back an odometer!")
def increment_odometer(self,miles):
self.odometer_reading+=miles
class Battery():
def __init__(self,battery_size=70):
self.battery_size=battery_size
def describe_battery(self):
print("This car has a "+str(self.battery_size)+"-kWh battery.")
class Electriccar(Car):
def __init__(self,make,model,year):
super().__init__(make,model,year)
self.battery_size=Battery()
my_tesla=Electriccar('tesla','model s',2016)
print(my_tesla.get_descriptive_name())
my_tesla.battery.describe_battery()
python版本：3.9
运行结果：
Traceback (most recent call last):
File "C:\Users\老大\Desktop\python\electric_car_1.py", line 31, in <module>
my_tesla.battery.describe_battery()
AttributeError: 'Electriccar' object has no attribute 'battery'
