code: def test_merge():
      input_node1 = ak.Input(shape=(30,))
      input_node2 = ak.Input(shape=(40,))
      output_node1 = ak.DenseBlock()(input_node1)
      output_node2 = ak.DenseBlock()(input_node2)
      output_node = ak.Merge()([output_node1, output_node2])
      output_node = ak.RegressionHead(shape=(1,))(output_node)
  
      model = graph_module.Graph(
          inputs=[input_node1, input_node2], outputs=output_node
      ).build(keras_tuner.HyperParameters())
      assert model.input_shape == [(None, 30), (None, 40)]
      assert model.output_shape == (None, 1)
  
file_path: autokeras/autokeras/graph_test.py
imports: import os
  import keras_tuner
  import pytest
  import autokeras
  from autokeras import graph
label_desc: Use image node_id 7 for calling a global function with example usage: test_merge() without return types