human
I found an interesting problem on https://www.codewars.com/kata/5a4bdd73d8e145f17d000035:
You get some nested lists. Keeping the original structures, sort only elements (integers) inside of the lists. In other words, sorting the intergers only by swapping their positions. 


```
Example
Input   : [[[2, 1], [4, 3]], [[6, 5], [8, 7]]]
Output  : [[[1, 2], [3, 4]], [[5, 6], [7, 8]]]
```

Note:
The structures of the lists are regular (symmetrical) and their depths are 3.

I tried it in Python, but could not do it. Can you solve it?

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Give me a the Python code you requested?
assistant
#Here is the Python code you requested.

from copy import deepcopy

def sort_nested_list(a):
    
    def seeker(lst):
        return lst if not lst or not isinstance(lst[0], list) else sum(map(seeker, lst), [])
        
    def putter(lst):
        for i in range(len(lst)):
            if isinstance(lst[i],list):
                putter(lst[i])
            else:
                lst[i] = next(elts)
        
    a, elts = deepcopy(a), iter(sorted(seeker(a)))
    putter(a)
    return a