Map MXNet's SoftmaxOutput operator attributes to onnx's Softmax operator
    and return the created node.

def convert_logistic_regression_output(node, **kwargs):
    """Map MXNet's SoftmaxOutput operator attributes to onnx's Softmax operator
    and return the created node.
    """
    name = node["name"]
    input1_idx = kwargs["index_lookup"][node["inputs"][0][0]]
    input1 = kwargs["proc_nodes"][input1_idx]
    sigmoid_node = onnx.helper.make_node(
        "Sigmoid",
        [input1.name],
        [name],
        name=name
    )
    return [sigmoid_node]