A cell timed out while it was being executed, after 1200 seconds.
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['# train loop', '', 'epoch = 5', 'for e in range(epoch):', '    print(f"Starting epoch {e} of {epoch}")']
...
['        reconstruction = net(X)', '        loss = criterion_MSE(reconstruction, X)', '        loss.backward()', '        optimizer.step()', '    print(f"Loss: {loss.item()}")']
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