How to convert FullGenerator to ONNX

Hello developers, I need to convert.pth to onnx type before deploying the model and implementing it on other platforms, but the conversion prompts that there are parts of the current model that cannot be converted by onnx. How can I solve this problem, thank you
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开发者你好，我在将模型部署与其他平台实现前需要将.pth转换为onnx类型，但转换时提示当前模型存在无法进行onnx转换的部分，请问我该如何解决，多谢