You are given two strings and you have to find an index of the second occurrence of the second string in the first one.
Let's go through the first example where you need to find the second occurrence... or which will point out that "s" is the first symbol in a word "sims" and therefore the index of the first occurrence is 0. But we have to find the second "s" which is 4th in a row and that means that the index of the second occurrence (and the answer to a question) is 3.
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
(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 --ff
checkio install-plugin --chromium