code: def test_model_summary_graph(self):
      x = Input(shape=(8,))
      y = Dense(10)(x)
      z = Dense(12)(y)
      model = Model(x, z)
      model.summary()
  
imports: import pytest
  import shutil
  from pyspark.sql.types import *
  from pyspark.sql.functions import lit
  from bigdl.dllib.feature.common import ChainedPreprocessing
  from bigdl.dllib.nncontext import *
  from bigdl.dllib.feature.image import *
  from bigdl.dllib.keras.layers import *
  from bigdl.dllib.keras.models import *
  from bigdl.dllib.nnframes import *
  from test.bigdl.test_zoo_utils import ZooTestCase
label_desc: Use image node_id 13 for calling the TestSimpleIntegration obj's underlying member method code with example usage: obj.test_model_summary_graph() without return types