I created a MUCH simpler example:
import torch
if __name__ == "__main__":
DEVICE = torch.device("cuda" if torch.cuda.is_available() else "cpu")
m = torch.nn.Linear(20, 30).to(DEVICE)
input = torch.randn(128, 20).to(DEVICE)
output = m(input)
print('output', output.size())
exit()
and get the same error.