Swap Nodes Swap Nodes
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The mission is in Reviewing Mode. You can't see the solutions Leader Board, but you can see other user solutions through the Random Review after you solve the mission.

Your task is to swap elements of the list (Iterable) pairwise. If you are given a list of 4 elements, then your function should return the same list, only in it the first and second elements are interchanged, as well as the third and fourth.

If there isn’t a paired amount of elements, then leave the last unpaired element in its place. An empty list should remain empty.

Input: Iterable.

Output: Iterable.


swap_nodes([1, 2, 3, 4]) == [2, 1, 4, 3]
swap_nodes([5, 5, 5, 5]) == [5, 5, 5, 5]
CheckiO Extensions

CheckiO Extensions allow you to use local files to solve missions. More info in a blog post.

In order to install CheckiO client you'll need installed Python (version at least 3.8)

Install CheckiO Client first:

pip3 install checkio_client

Configure your tool

checkio --domain=py config --key=

Sync solutions into your local folder

checkio sync

(in beta testing) Launch local server so your browser can use it and sync solution between local file end extension on the fly. (doesn't work for safari)

checkio serv -d

Alternatevly, you can install Chrome extension or FF addon

checkio install-plugin
checkio install-plugin --ff
checkio install-plugin --chromium

Read more here about other functionality that the checkio client provides. Feel free to submit an issue in case of any difficulties.

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