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: [277, 412, 88, 399, 406, 323, 449, 20, 33, 443, 418, 405, 254, 224, 390, 269, 61, 146, 203, 195]
A: 
[277, 412, 88, 399, 406, 323, 20, 449, 33, 443, 418, 405, 254, 224, 390, 269, 61, 146, 203, 195]