Export summarization pipeline to ONNX

Can you please help me exporting summarization-pipeline to ONNX?
I looked at the notebook exemplifying how to export NER pipeline to ONNX (please refer to NLP Transformers pipelines with ONNX | by Thomas Chaigneau | Towards Data Science).

In the NER example, a class was inherited from TokenClassificationPipeline, and the method _forward was overrided, such that “self.model(model_inputs.data)” was replaced by “session.run(output_names=[outputs_name], input_feed=inputs)” . (inputs is a conversion of inputs_data to numpy arrays.)

Trying to mimic the procedure to Summarization, my problem:
I inherited a class from SummarizationPipeline, and then tried to override the _generate method. However, I do not succeed to replace “self.tokenizer.decode(…)” with “session.run(…)”. Any idea please?
Thank you,