Libtorch, calling the jit.export method

In my case,

class NN(nn.Module):
    @torch.jit.unused
    def forward(self):
        pass

    @torch.jit.export
    def another(self):
        pass

nn = NN()
scripted = torch.jit.script(nn)
scripted.another()

It works fine on the Python(In real, much more complex structure)

But In cpp(libtorch),

error: ‘using Module = struct torch::jit::Module {aka struct torch::jit::Module}’ has no member named ‘another’

How can I call the another in cpp level?