I did the following
def register_hooks(self):
"""Register forward and backward hook to Conv module."""
    self.forward_hooks, self.backward_hooks= [], []
    for module, name in self.conv_names.items():
        self.forward_hooks.append(module.register_forward_hook(self.save_input_forward_hook))
        self.backward_hooks.append(module.register_full_backward_hook(self.compute_fisher_backward_hook)

def remove_hooks(self):
    for fh in self.forward_hooks:
        fh.remove()
    for bh in self.backward_hooks:
        bh.remove() 

Then I remove hooks and try to save the model
torch.save(deepcopy(model).half(), path)

and I have the following error
AttributeError: 'Conv2d' object has no attribute 'modified_forward'

I will be grateful if you help me!