Retrun data type of torch.fx.tracer.trace()

Hi,
according to the instruction here: torch.fx — PyTorch main documentation
the return data of torch.fx.tracer.trace() and torch.fx.symbolic_trace() is graph.
however, the data type of fx_model is GraphModule in the following code:

    fx_model = torch.fx.symbolic_trace(model)
    modules = dict(fx_model.named_modules())
    for node in fx_model.graph.nodes:
        if node.target in modules:
            print(node.target)
            if type(modules[node.target]) == torch.nn.Conv2d:
                print('conv node')