In this task, you are given a list of unique integers you need to swap the positions of maximum and minimum element in the list and return the updated list.

Example Input: [142, 384, 19, 322, 397, 411, 65, 214, 114, 75, 52, 40, 122, 337, 350, 289, 42, 236, 91, 386]
Example Output: [142, 384, 411, 322, 397, 19, 65, 214, 114, 75, 52, 40, 122, 337, 350, 289, 42, 236, 91, 386]

Example Input: [477, 200, 377, 405, 450, 137, 333, 139, 195, 52, 445, 154, 61, 63, 441, 455, 308, 354, 19, 340]
Example Output: [19, 200, 377, 405, 450, 137, 333, 139, 195, 52, 445, 154, 61, 63, 441, 455, 308, 354, 477, 340]

Example Input: [371, 401, 57, 175, 193, 59, 392, 179, 313, 25, 280, 369, 173, 345, 464, 247, 132, 121, 13, 208]
Example Output:
[371, 401, 57, 175, 193, 59, 392, 179, 313, 25, 280, 369, 173, 345, 13, 247, 132, 121, 464, 208]