code: def export_onnx(self):
      sym = os.path.join(
          self.param_path, self.model_name + self.symbol_suffix
      )
      params = os.path.join(
          self.param_path, self.model_name + self.params_suffix
      )
      return onnx_mxnet.export_model(
          sym, params, [self.input_shape], np.float32, self.onnx_model
      )
  
file_path: gluon-cv/tests/onnx/test_inference.py
label_desc: Use image node_id 6 for calling the Model obj's underlying member method code with example usage: obj.export_onnx() and returns: onnx_mxnet