我遇到了困难,无法确定为什么会出现这个错误。我的代码是这样的:
#define the Animal Class
class Animal:
def __init__ (self, animal_type, age, color):
self.animal_type = animal_type
self.age = age
self.color = color
def makeNoise():
pass
def __str__(self):
print ("% is % years old and is %" % animal_type,age, color)
#define child classes of Animal
class Wolves(Animal):
def __init__(self, animal_type, age, color, wild):
Animal.__init__(self, animal_type, age, color)
self.wild = wild
def __str__(self):
print ("% is % years old and is % and is %" % (animal_type, age, color, wild))
class Bear(Animal):
def __init__ (self, animal_type, age, color, sex):
self.sex = sex
Animal.__init__(self,animal_type, age, color)
class Moose(Animal):
def __init__(self, animal_type, age, color, antlers):
self.antlers = antlers
Animal.__init__(self, animal_type, age, color)
#add items to each class
wally = Wolves("wolf", 4, "grey","wild")
sally = Wolves("wolf", 3, "white", "tame")
print (str(sally))
print (str(wally))
完整的异常追踪信息如下
Traceback (most recent call last):
File "//mgroupnet.com/RedirectedFolders/SBT/Documents/bear51.py", line 41, in <module>
print (str(sally))
File "//mgroupnet.com/RedirectedFolders/SBT/Documents/bear51.py", line 24, in __str__
print ("% is % years old and is % and is %" % (animal_type, age, color, wild))
NameError: name 'animal_type' is not defined
我做错了什么?
self.animal_type
,self.age
,self.color
来调用实例属性。 - R Nar