ok, thank you Sir. I got it.
but I got another error:

RuntimeError                              Traceback (most recent call last)
/tmp/ipykernel_59/2520602840.py in 
128
129 if name==“main”:
 → 130     main()
/tmp/ipykernel_59/2520602840.py in main()
78             batch = batch.to(“cuda”)
79             optimizer.zero_grad()
—> 80             outputs = model(batch)
81             loss = criterion(outputs,batch.tensor)
82             loss.backward()


RuntimeError: “addmm_cuda” not implemented for ‘Byte’