Python Element Swap Coding | Dataford Interview Questions

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Problem

Teamware Solutions processes ordered items in Python lists and occasionally needs to exchange two positions without creating a second list. Implement a function that swaps the elements at two provided indices in place and returns the modified list.

Formal Specification

Implement swap_elements(arr, index1, index2).

Input: arr, a list of integers, and two valid zero-based integer indices, index1 and index2.
Output: The same list object after the values at index1 and index2 have been exchanged.
The function must not change the list length or the values at any other positions.
If both indices are equal, the list remains unchanged.

Constraints

1 <= len(arr) <= 10^5
-10^9 <= arr[i] <= 10^9
0 <= index1, index2 < len(arr)
The input indices are valid
The list must be modified in place

Function Signature

def swap_elements(arr, index1, index2):