I am trying like this.
transf = transforms.Compose([transforms.Resize(255),
                             transforms.ToTensor(),
                             transforms.Normalize((0.5,0.5,0.5),(0.5,0.5,0.5))
                            ])

trainloader = torch.utils.data.DataLoader(train_dataset, batch_size = 8, shuffle=True )
data_iter = iter(trainloader)
images, labels = next(data_iter)
fig, axes = plt.subplots(figsize = (10,4), ncols=4)
for ii in range(4):
    ax = axes[ii]
    helper.imshow(images[ii], ax=ax, normalize=False)

But getting this error

RuntimeError: invalid argument 0: Sizes of tensors must match except in dimension 0. Got 406 and 513 in dimension 3 at c:\a\w\1\s\tmp_conda_3.6_091443\conda\conda-bld\pytorch_1544087948354\work\aten\src\th\generic/THTensorMoreMath.cpp:1333