I) Thank you for responding to my message because it makes me happy to know that my message was read by your team. II) The “.okular” file is an archive made by “Okular software” and contains the “PDF” file with its annotations. “https://okular.kde.org/” this is the link to the software, I work with “openSUSE” “https://www.opensuse.org/”. III) For someone who wants to learn programming language and chose “Python” to start with it, Having a good tutorial is a crucial moment. Me as an example, I don’t follow any study in informatics field so I build my knowledge thanks to my efforts, In consequence I don’t have a strong base in programming language. Even that I found some parts in “Python Language Reference” and “Python library reference” easy to learn for someone like me. I suggest to aggregate those informations and add them to the “Python tutorial” to build a strong introduction to your great language “Python”.