`concept2sentence` by default assumes that a CUDA device is available for pytorch

[Saad-Mahamood]

In the __init__ on line 42:

device='cuda'

This transformation always assumes that a CUDA device is available. However, it should check first to see if a CUDA device available using this helper function from pytorch: https://pytorch.org/docs/stable/generated/torch.cuda.is_available.html

If not, then CPU should be used instead.