code: def NetFxSdkDir(self):
          
          for ver in self.NetFxSdkVersion:
              loc = os.path.join(self.ri.netfx_sdk, ver)
              sdkdir = self.ri.lookup(loc, 'kitsinstallationfolder')
              if sdkdir:
                  break
          return sdkdir or ''
docs: Microsoft .NET Framework SDK directory.