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I have my code which does a quick sort on a list of values:

```
def Quick_sort_random(random_list):
r = random_list.copy()
def inner(r):
if len(r) < 2:
return r
p = random.randint(0, len(r) - 1)
pivot = r[p]
left = list(filter(lambda x: x <= pivot, r[:p] + r[p + 1:]))
right = list(filter(lambda x: x > pivot, r[:p] + r[p + 1:]))
return Quick_sort_random(left) + [pivot] + Quick_sort_random(right)
a = inner(r)
return random_list,a
```

This throws the error:

```
TypeError: can only concatenate tuple (not "list") to tuple
```

I have the inner() function because I want to return both the original list and the sorted list. How can I fix this?

### >Solution :

Your `Quick_sort_random`

function returns a tuple but you only need the second item in it for the sorting. Change the last line in `inner`

to:

```
return Quick_sort_random(left)[1] + [pivot] + Quick_sort_random(right)[1]
```