You will be given a definition of a task first, then some input of the task.
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.

[162, 27, 140, 274, 414, 376, 104, 159, 418, 155, 493, 151, 422, 335, 187, 292, 217, 31, 248, 84]
Output:
[162, 493, 140, 274, 414, 376, 104, 159, 418, 155, 27, 151, 422, 335, 187, 292, 217, 31, 248, 84]