3、解决“TypeError: 'tuple' object cannot be interpreted as an integer"错误提示 4、解决“lOError: File not open for writing” 错误提示 5、解决“SyntaxError:invalid syntax” 错误提示 6、解决“TypeError: 'str' object does not support item assignment”错误提示 7、解决 “TypeError: Can't convert...
defgreet(self,loud=False):ifloud:print('HELLO, %s!'%self.name.upper())else:print('Hello, %s'%self.name)g=Greeter('Will')# Construct an instanceofthe Greeterclassg.greet()# Call an instance method;prints"Hello, Will"g.greet(loud=True)# Call an instance method;prints"HELLO, WILL!" ...
再使用for,会从第三个元素2开始输出 2 3 4 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 从结果可以看出,for 循环实际上就是调用了迭代器的 __next__方法,当捕捉到 MyListIterator 异常时自动结束 for 循环 创建一个可迭代对象 class MyList(object)...
r=range(1,6)#先定义一个 range 对象foriinr:forjinr:# 双重循环print((i,j),end=' ') # end=' ' 是不换行的意思print()# 只打印一个换行 这很简单。但如果用咱们编的这个 Range,问题就出来了,看输出: (1,2)(1,3)(1,4)(1,5) 问题就出在:因为有 return self 的存在,两个 for 循环共用...
(self):# For simplicity's sake, we ignore complex# seating arrangement for first-classreturnrange(1,56),"ABCDEGHJK"defcard_printer(passenger,seat,flight_number,aircraft):output=(f"| Name:{passenger}"f" Flight:{flight_number}"f" Seat:{seat}"f" Aircraft:{aircraft}"f" |")banner='+'+'...
x=self.aself.a+=1returnxelse:raiseStopIterationmyclass=MyNumbers()myiter=iter(myclass)forxinmy...
classSubject: def__init__(self): self._observers=[] defattach(self,observer_func): self._observers.append(observer_func) defnotify(self,*args,**kwargs): forobserver_funcinself._observers: observer_func(*args,**kwargs) classObserver: ...
6else: 7returny 8print(maximum(2,3)) 9(源文件:code/func_return.py) 10输出 11$ python func_return.py 123 没有返回值的return语句等价于return None。None是Python中表示没有任何东西的特殊 类型。例如,如果一个变量的值为None,可以表示它没有值。 除非你提供你自己的return语句,每个函数都在结尾暗含...
class MyClass(): def __iter__(self): pass if __name__ == "__main__": m = MyClass() print(isinstance(m, Iterable))# 判断是否为可迭代对象 运行结果: True 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
Objects are instances of a class (for example, the class “cars”) and have methods and attributes. This contrasts with languages that center on a series of functions. Moreover, Python is defined as a high-level programming language (in opposition to low-level languages, such as assembly),...