Building nbPython from sources is not trivial. But neither is it "rocket science". The links below should enable you to build and test-drive the nbPython-enabled NetBeans IDE using "Ant tryme". PLEASE note well that a typical build environment will require at LEAST 12 GB of available disk space!
Building nbPython References
- To learn specifically how to build Python support, visit NbPythonHgBuild
- To learn about building from sources (generally) visit WorkingWithNetBeansSources
- To learn about developing NetBeans modules, visit NetBeans Platform Plugin Quick Start