python - How to convert line simple features to topological network?

using Gdal/ OGR is there a way to convert a shp, kml, or PostGIS line layer into a network of nodes and segments so it can be used in packages such as networkx?

Answer

Ben Reilly recently posted a link on another question to his utilitynetwork Python package, which uses the OGR bindings to convert data into networkx DiGraphs.