Hello,
I also encounter this error.
My images are 256x256 8bpp PNG files.
Curious thing is, I am running same code on 2 different PCs and it works on the non-CUDA system.
With the CUDA-enabled system,  if I add the scale operation first,
'train': transforms.Compose([ transforms.Scale((64, 64)), transforms.ToTensor() ]),
I get the error message: TypeError: unsupported operand type(s) for /: 'tuple' and 'int'
If I first convert to tensor and then scale,
'train': transforms.Compose([ transforms.ToTensor(), transforms.Scale((64, 64)) ]),
I get the TypeError: 'builtin_function_or_method' object is not iterable error.
Finally, as @ritchieng found out, if I remove the scaling, it works without any problems.
Best regards,
Sel