Suggestion on page 392

[baifanhorst]

On page 392, the loss function is defined as:

def loss_fn(input, target):
return (input-target).pow(2).mean()

Since 'input' is the name of a built-in function in python, perhaps another name should be used, for example, 'prediction'. The codes then become

def loss_fn(prediction, target):
return (prediction-target).pow(2).mean()