class Net(nn.Module):
    def __init__(self):
        super().__init__()
        self.blocks = [nn.Linear(10, 64), nn.Linear(64, 64), nn.Linear(64, 64)]   # plain list
        self.head = nn.Linear(64, 3)

    def forward(self, x):
        for layer in self.blocks:
            x = torch.relu(layer(x))
        return self.head(x)