Hello @ritchieng,
For me this issue was caused by an old (v0.1.8) torchvision package from pip. In that package, scale function was not checking the type of size if it is an int or not.
I have installed it from sources (master branch) and the problem of TypeError: unsupported operand type(s) for /: 'list' and 'int' is resolved.
Regards,
Sel