onnxruntime

2de58077 - Attention fusion for UNet onnx model export from PyTorch 2.* (#16629)

Attention fusion for UNet onnx model export from PyTorch 2.* (#16629) ### Description Tested with stable diffusion unet models exported by pytorch nightly. Example to run: ``` cd onnxruntime/python/tools/transformers/ python optimizer.py --input unet.onnx --output unet_fp16.onnx --model_type unet --float16 --opt_level 0 ```