I know this is a bit off topic, but it might be related to graph-tool also there might be someone here who could help me. I need all the planar graphs that are 4-regular (in the meaning that every vertex has a degree 4) but each graph is allowed to have double edges (not triple or more) also an edge can connect to the same vertex. I couldn't find any database that could give these to me so probably I will have to generate them for myself. Any idea of how could I do this with graph-tool? I know how can I check weather these graphs are planar or not, but the rest seems very complicated. Any help is very much appreciated.