Given the task definition and input, reply with output. 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.

[338, 79, 27, 229, 433, 471, 328, 497, 474, 322, 424, 42, 341, 393, 32, 479, 280, 493, 428, 103]
[338, 79, 497, 229, 433, 471, 328, 27, 474, 322, 424, 42, 341, 393, 32, 479, 280, 493, 428, 103]