pytorch version 1.7.0
GPU - Tesla V100
NVIDIA-SMI 440.100      Driver Version: 440.100      CUDA Version: 10.2
Regarding the values you wanted for y_hat and t, the prints was made from within the forward in the loss function:

y_hat
torch.Size([12, 14])
(14, 1)
0

t
torch.Size([12, 14])
(14, 1)
0

Anything else you need?