code: def test_correctness_two_states_stack(self):
      sequence = np.arange(24).reshape((2, 3, 4)).astype("float32")
      layer = layers.RNN([TwoStatesRNNCell(3), TwoStatesRNNCell(2)])
      output = layer(sequence)
      self.assertAllClose(
          np.array([[3144.0, 3144.0], [17544.0, 17544.0]]), output
      )
  
      layer = layers.RNN(
          [TwoStatesRNNCell(3), TwoStatesRNNCell(2)],
          return_sequences=True,
      )
      output = layer(sequence)
      self.assertAllClose(
          np.array(
              [
                  [[72.0, 72.0], [624.0, 624.0], [3144.0, 3144.0]],
                  [
                      [648.0, 648.0],
                      [4080.0, 4080.0],
                      [17544.0, 17544.0],
                  ],
              ]
          ),
          output,
      )
  
      layer = layers.RNN(
          [TwoStatesRNNCell(3), TwoStatesRNNCell(2)], return_state=True
      )
      output, state_1, state_2 = layer(sequence)
  
      self.assertAllClose(
          np.array([[3144.0, 3144.0], [17544.0, 17544.0]]), output
      )
      self.assertAllClose(
          np.array([[158.0, 158.0, 158.0], [782.0, 782.0, 782.0]]),
          state_1[0],
      )
      self.assertAllClose(
          np.array([[158.0, 158.0, 158.0], [782.0, 782.0, 782.0]]),
          state_1[1],
      )
      self.assertAllClose(
          np.array([[1572.0, 1572.0], [8772.0, 8772.0]]), state_2[0]
      )
      self.assertAllClose(
          np.array([[1572.0, 1572.0], [8772.0, 8772.0]]), state_2[1]
      )
  
file_path: keras/keras/layers/rnn/stacked_rnn_cells_test.py
imports: import numpy
  import pytest
  from keras import layers
  from keras import testing
  from keras.layers.rnn.rnn_test import OneStateRNNCell
  from keras.layers.rnn.rnn_test import TwoStatesRNNCell
label_desc: Use image node_id 3 for calling the StackedRNNTest obj's underlying member method code with example usage: obj.test_correctness_two_states_stack() without return types