code: def test_unknown_rank(self):
      # This test uses placeholders and does not work in eager mode.
      if context.executing_eagerly():
          return
      signal = array_ops.placeholder_with_default(
          np.ones((4, 3, 5)).astype(np.int32), shape=None
      )
      frame_step = array_ops.placeholder_with_default(2, shape=[])
      reconstruction = reconstruction_ops.overlap_and_add(
          signal, frame_step
      )
  
      self.assertEqual(reconstruction.shape, None)
      expected_output = np.array([[1, 1, 2, 2, 3, 2, 2, 1, 1]] * 4)
      self.assertAllClose(reconstruction, expected_output)
  
imports: from absl.testing import parameterized
  import numpy
  from tensorflow.python.eager import context
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import array_ops_stack
  from tensorflow.python.ops import gradient_checker_v2
  from tensorflow.python.ops import gradients_impl
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops.signal import reconstruction_ops
  from tensorflow.python.platform import test
label_desc: Use image node_id 4 for calling the ReconstructionOpsTest obj's underlying member method code with example usage: obj.test_unknown_rank() without return types