Why Does `list.sort()` Return `None` in Python?

Understanding the Behavior of "return list.sort()": Why It Returns None Instead of the Updated List

The question pertains to a Python function called findUniqueWords that sorts a list of strings and attempts to return the sorted list. However, the function currently returns None instead of the sorted list. Let's delve into why this occurs and provide a solution.

In the provided code, the line answer = newList.sort() assigns to answer the result of calling sort() on newList. However, the sort() method in Python doesn't create a new list. Instead, it modifies the original list in place, meaning that newList becomes sorted, but there is no new object to return. As result, the return statement returns the value None instead of the updated newList.

To rectify this issue and return the sorted list correctly, we need to write:

newList.sort()
return newList

By separating the sort operation and the return statement, we ensure that the updated list is returned instead of None. This modification will enable the findUniqueWords function to return the expected sorted list of unique words.

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