为什么用python启动omnet显示找不到.ned文件
Loading NED files from D:\omnet\samples\aweixing\Node.ned:
<!> Error: Could not load NED sources from 'D:\omnet\samples\aweixing\Node.ned': Cannot temporarily change to directory 'D:\omnet\samples\aweixing\Node.ned': Invalid argument
End.
OMNeT++ 启动失败: Command '['D:\omnet\bin\opp_run.exe', '-u', 'Cmdenv', '-f', 'D:\omnet\samples\aweixing\omnetpp.ini', '-n', 'D:\omnet\samples\aweixing\Node.ned']' returned non-zero exit status 1.
ned文件路径要怎么配置啊