remove useless make_model

Author: nbcsm

tests/run_pretrained_models.py

@@ -251,8 +251,8 @@ def run_test(self, name, backend="caffe2", onnx_file=None, opset=None, extra_ops
                 # convert model to onnx
                 onnx_graph = self.to_onnx(sess.graph, opset=opset, extra_opset=extra_opset,
                                           shape_override=shape_override, input_names=inputs.keys())
+                onnx_graph = optimizer.optimize_graph(onnx_graph)
                 model_proto = onnx_graph.make_model("converted from tf2onnx")
-                model_proto = optimizer.optimize_graph(onnx_graph).make_model("optimized")
                 logger.info("To_ONNX, OK")
                 if onnx_file:
                     self.create_onnx_file(name, model_proto, inputs, onnx_file)