human
Give me a the Python program you requested given the following:
2. CAM
assistant
#Here is the Python program you requested.
class SaveFeatures():
    features=None
    def __init__(self, m): self.hook = m.register_forward_hook(self.hook_fn)
    def hook_fn(self, module, input, output): self.features = to_np(output)
    def remove(self): self.hook.remove()

x,y = next(iter(data.val_dl))
x,y = x[None, 1], y[None, 1]

vx = Variable(x.cuda(), requires_grad=True)

dx = data.val_ds.denorm(x)[0]
plt.imshow(dx);

sf = SaveFeatures(m[-4])
py = m(Variable(x.cuda()))
sf.remove()

py = np.exp(to_np(py)[0]); py

feat = np.maximum(0, sf.features[0])
feat.shape