我需要遍历pandas.series对象流（我想使用的对象类型与此无关）。可选地，对每个序列应用一个任意函数，并且-这里是clincher-这个任意函数可以是生成函数，生成两个（或更多）值。我对未来充满希望 more_itertools.flatten 函数，但它没有帮助，因为它会在常规函数或没有函数Map到生成器时中断。有没有办法把这个iterable变成一个简单的系列对象生成器？下面是一个简单的例子，说明了这个问题：

In [1]: from more_itertools import flatten
   ...: 
   ...: def generator():
   ...:     for i in range(10):
   ...:         yield i
   ...: 
   ...: def postprocess1(i):
   ...:     yield 2*i
   ...: 
   ...: def postprocess1_return(i):
   ...:     return 2*i
   ...: 
   ...: def postprocess2(i):
   ...:     yield from (i, 2*i)
   ...: 
In [2]: list(generator())
   ...: 
Out[2]: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
In [3]: list(map(postprocess1, generator()))
   ...: 
Out[3]: 
[<generator object postprocess1 at 0x7f5a402916d0>,
 <generator object postprocess1 at 0x7f5a40291e40>,
 <generator object postprocess1 at 0x7f5a40291f20>,
 <generator object postprocess1 at 0x7f5a40291dd0>,
 <generator object postprocess1 at 0x7f5a40291eb0>,
 <generator object postprocess1 at 0x7f5a40209040>,
 <generator object postprocess1 at 0x7f5a40209190>,
 <generator object postprocess1 at 0x7f5a402092e0>,
 <generator object postprocess1 at 0x7f5a402090b0>,
 <generator object postprocess1 at 0x7f5a40209350>]
In [4]: list(map(postprocess1_return, generator()))
   ...: 
Out[4]: [0, 2, 4, 6, 8, 10, 12, 14, 16, 18]
In [5]: list(map(postprocess2, generator()))
   ...: 
Out[5]: 
[<generator object postprocess2 at 0x7f5a403ad430>,
 <generator object postprocess2 at 0x7f5a40209580>,
 <generator object postprocess2 at 0x7f5a402097b0>,
 <generator object postprocess2 at 0x7f5a40209510>,
 <generator object postprocess2 at 0x7f5a40209430>,
 <generator object postprocess2 at 0x7f5a40209740>,
 <generator object postprocess2 at 0x7f5a402096d0>,
 <generator object postprocess2 at 0x7f5a40209820>,
 <generator object postprocess2 at 0x7f5a40209660>,
 <generator object postprocess2 at 0x7f5a40209890>]
In [6]: list(flatten(generator()))
   ...: 
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-6-7cd770547fa4> in <module>
----> 1 list(flatten(generator()))
TypeError: 'int' object is not iterable
In [7]: list(flatten(map(postprocess1, generator())))
   ...: 
Out[7]: [0, 2, 4, 6, 8, 10, 12, 14, 16, 18]
In [8]: list(flatten(map(postprocess1_return, generator())))
   ...: 
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-8-35ce9aef7285> in <module>
----> 1 list(flatten(map(postprocess1_return, generator())))
TypeError: 'int' object is not iterable
In [9]: list(flatten(map(postprocess2, generator())))
Out[9]: [0, 0, 1, 2, 2, 4, 3, 6, 4, 8, 5, 10, 6, 12, 7, 14, 8, 16, 9, 18]