[转]迭代器（Iterator）和可迭代对象（Iterable）

1     def __iter__(self):
2 
3         return iter(self._tests)

 1 class ProblemB(object):
 2     def __init__(self):
 3         # 初始化数列计数器
 4         self.count = 0
 5         self._length = 0
 6     @property
 7     def length(self):
 8         return self._length
 9     @length.setter
10     def length(self, value):
11         if not isinstance(value,int):
12             raise ValueError("length must be a integer!")
13         if value < 1 or value > 100:
14             raise ValueError("length must between 1 ~ 100!")
15         self._length = value
16      def __iter__(self):
17         return self
18      def __next__(self):
19         if self.count >= self.length:
20             raise StopIteration()
21         self.count = self.count + 1
22         self.value = self.count * 2 - 1
23         return self.value
24    def solution(sample):
25     solu_iter = ProblemB()
26     solu_iter.length = sample
27     sum = 0
28     for i in solu_iter:
29         sum += i
30     return sum
31  print (solution(10)