I was trying to set up path to be able to call qgis modules as it defined in their website Introduction and set PYTHONPATH=c:\qgispath\python .
However, I still get import error. I want to be able to call this module from Spider or Python idle under arcgis. Does anyone know how to do that or have more detailed explained documentation? I can call the arcpy from spider but I could not achieve that for qgis.core module.