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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_layer(node, **kwargs):
 """Convert MXNet layer to ONNX"""

        op = str(node["op"])
        if op not in MXNetGraph.registry_:
            raise AttributeError("No conversion function registered for op type %s yet." % op)
        convert_func = MXNetGraph.registry_[op]
        return convert_func(node, **kwargs)