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.

[53, 400, 447, 274, 435, 432, 46, 51, 317, 404, 442, 16, 70, 190, 449, 43, 356, 156, 175, 294]
[53, 400, 447, 274, 435, 432, 46, 51, 317, 404, 442, 449, 70, 190, 16, 43, 356, 156, 175, 294]