Better way to swap elements in a list?

Question

I have a bunch of lists that look like this one:

l = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

I want to swap elements as follows:

fi         


        

Answer 1

Here a solution based in the modulo operator:

l = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
even = []
uneven = []
for i,item in enumerate(l):
    if i % 2 == 0:
        even.append(item)
    else:
        uneven.append(item)

list(itertools.chain.from_iterable(zip(uneven, even)))