>>> class A:
...     
...     def __iter__(self):
...         self.it = iter('abc')
...         return self
...     
...     def __next__(self):
...         return next(self.it) * 8
... 
>>> a = A()
>>> for i in a:
...     print(i)
... 
aaaaaaaa
bbbbbbbb
cccccccc
>>>