### Tell us what’s happening:

I am missing the nuance of the request. The while loop seems ok, but “an element” of the left_ or right_ part seems arbitrary, so I picked the first one…

### Your code so far

```
def merge_sort(array):
middle_point = len(array) // 2
left_part = array[:middle_point]
right_part = array[middle_point:]
merge_sort(left_part)
merge_sort(right_part)
left_array_index = 0
right_array_index = 0
sorted_index = 0
# User Editable Region
while left_array_index < len(left_part) and right_array_index < len(right_part)
if left_part[1] < right_part[1]:
array.append(left_part[1])
else:
array.append(right_part[1])
# User Editable Region
```

### Your browser information:

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36`

### Challenge Information:

Learn Data Structures by Building the Merge Sort Algorithm - Step 11