Helllo,
I ve found this code: auto-attack/eval.py at master · fra31/auto-attack · GitHub 2
    transform_list = [transforms.ToTensor()]
    transform_chain = transforms.Compose(transform_list)
    item = datasets.CIFAR10(root=args.data_dir, train=False, transform=transform_chain, download=True)
    test_loader = data.DataLoader(item, batch_size=1000, shuffle=False, num_workers=0)

Is the dataset already normalized by std mean and std var?