the command prompt is false
the true commande is "pip3 install python-igraph"
but it dont work anyway, it don't build the .bin file
This project is abandoned and had problems from the beginning.
For example, I made the assumption that I can include SGDK with it, but this did not work, and I was fooled that it works as it was using the installation I had.
So for this to work you will have to install SGDK and then make all the changes in the source to support the current version (those are very easy changes).
I was planning to make another game with it, but it turned out to be too difficult to keep track of the actions and abandoned the idea and the project all together.
Sorry for wasting your time, I will update the game page with those infos.