Export longformer to ONNX
Hi :) I need to convert a pre-trained pytorch model to tensorflow 2. I'm trying to follow these instructions https://huggingface.co/docs/transformers/serialization#exporting-a-model-to-onnx (export to onnx first).

But I'm having this error:

KeyError: "longformer is not supported yet. Only ['albert', 'bart', 'mbart', 'bert', 'ibert', 'camembert', 'distilbert', 'marian', 'm2m-100', 'roberta', 't5', 'xlm-roberta', 'gpt2', 'gpt-neo', 'layoutlm', 'electra'] are supported. If you want to support longformer please propose a PR or open up an issue."

Is it possible to add support to longformer, please? Thanks


> Is it possible to add support to longformer, please? Thanks

Hey @anasilvasd we have created a group recently that aims to add ONNX support for all models on the hub. Maybe you could help us by doing the implementation yourself?

Here is the link of the issue relating all the models that need help #16308
And here is the HF org if you want to join us: [ONNXConfig for all](https://huggingface.co/OWG)

You will find help on implementation by reading issue post and looking at others implementation linked in the issue below. Have a great week-end<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.