Create a function (MaximumSwap) that, given any list of integers list, returns a list with the same
elements as list, except that the first element has been swapped with the maximum element in list.
Note: This function should not print the list, but return it.
Example output for list = [1, 2, 3, 4]:
>>> MaximumSwap ([1,2,3,4])
[4,2,3,1]
Example output for list = [5, 8, 3, 21, 7, 4, 14]:
>>> MaximumSwap ([5,8,3,21,7,4,14])
[21,8,3,5,7,4,14]