pop-up windows in graph-tool

Good time to you, dear graph-tool author.

Im trying to make graph layout for different planning algorithms on
python3. I made this normally, but I need to create a pop-up window,
that will blow up after click on vertex, with text from propety of
vertex. I didnt find any material for this in WEB, can you give me some
advises about that?

Although this is possible to do, it is currently completely
undocumented.

At the moment, the best you can do is look into the source code, and try
to figure it out.

Best,
Tiago