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