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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convert_slice_axis(node, **kwargs):
 """Map MXNet's slice_axis operator attributes to onnx's Slice operator and return the created node. """

    name, input_nodes, attrs = get_inputs(node, kwargs)

    axes = int(attrs.get("axis"))
    starts = int(attrs.get("begin"))
    ends = int(attrs.get("end", None))
    if not ends:
        raise ValueError("Slice: ONNX doesnt't support 'None' in 'end' attribute")

    node = onnx.helper.make_node(
        "Slice",
        input_nodes,
        [name],
        axes=[axes],
        starts=[starts],
        ends=[ends],
        name=name,
    )
    return [node]