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.

Example Input: [304, 238, 225, 39, 179, 446, 165, 139, 69, 450, 51, 374, 188, 193, 68, 259, 433, 464, 127, 63]
Example Output: [304, 238, 225, 464, 179, 446, 165, 139, 69, 450, 51, 374, 188, 193, 68, 259, 433, 39, 127, 63]

Example Input: [282, 38, 402, 29, 79, 187, 434, 308, 398, 386, 470, 358, 266, 214, 145, 115, 380, 66, 20, 136]
Example Output: [282, 38, 402, 29, 79, 187, 434, 308, 398, 386, 20, 358, 266, 214, 145, 115, 380, 66, 470, 136]

Example Input: [442, 236, 497, 400, 458, 262, 338, 325, 251, 129, 425, 385, 465, 482, 345, 372, 337, 461, 486, 310]
Example Output:
[442, 236, 129, 400, 458, 262, 338, 325, 251, 497, 425, 385, 465, 482, 345, 372, 337, 461, 486, 310]

