Pytorch moved zero_gradients out of gradcheck (apparently?)

[bwbellmath]

installing torchattacks from scratch on a fresh HPC environment, I hit the error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".../.conda/envs/stabn/lib/python3.8/site-packages/torchattacks/__init__.py", line 17, in <module>
    from .attacks.fab import FAB
  File ".../.conda/envs/stabn/lib/python3.8/site-packages/torchattacks/attacks/fab.py", line 12, in <module>
    from torch.autograd.gradcheck import zero_gradients
ImportError: cannot import name 'zero_gradients' from 'torch.autograd.gradcheck' (.../.conda/envs/stabn/lib/python3.8/site-packages/torch/autograd/gradcheck.py)

Notably, when investigating the gradcheck.py file, zero_gradients is no longer defined within and a significant refactor was mentioned in the relasenotes for pytorch version 1.9 17 days ago

I think I can just use the LTS release which seems not to have this change, but I think it's notable enough to raise as an issue.

[Harry24k]

Thank you. Solved by implementing zero_gradients from the old version of PyTorch. Please refer to v3.0.0.