# Codeblock 3
spp = SPP()

x = torch.tensor([[[[5, 4, 4, 5, 3, 2, 6, 5],
                    [2, 8, 6, 3, 1, 5, 8, 1],
                    [4, 3, 7, 5, 2, 4, 7, 3],
                    [2, 1, 3, 2, 5, 5, 4, 2],
                    [4, 6, 7, 9, 5, 6, 6, 7],
                    [6, 8, 5, 9, 4, 9, 4, 1],
                    [3, 7, 4, 6, 8, 4, 4, 9],
                    [2, 4, 4, 3, 8, 2, 9, 2]]]], dtype=torch.float32)  #(1)

out = spp(x)    #(2)