GraphView of an exported onnx model is empty

MAIN BRANCH

I tried to export the simple MNIST model from AIDGE to ONNX. My code is attached. The ONNX export works but when I try to import the ONNX model in order to work with it, the GraphView is empty (see figure bellow). So it seems that the "aidge_onnx.export_onnx" doesn't work well exporting an empty model. model_onnx_test.ipynb