code: def test_subnetwork_in_mlp_network(self):
      network = layers.join(
          layers.Input(2),
          layers.Relu(10),
          layers.Relu(4) >> layers.Relu(7),
          layers.Relu(3) >> layers.Relu(1),
      )
  
      self.assertEqual(len(network), 6)
      self.assertTrue(network.is_sequential())
      self.assertShapesEqual(network.input_shape, (None, 2))
      self.assertShapesEqual(network.output_shape, (None, 1))
  
file_path: neupy/tests/layers/graph/test_subnetworks.py
imports: import numpy
  from neupy import layers
  from neupy.utils import asfloat
  from base import BaseTestCase
label_desc: Use image node_id 1 for calling the SubnetworksTestCase obj's underlying member method code with example usage: obj.test_subnetwork_in_mlp_network() without return types