code: def testUnknownDimension(self):
      dim = tensor_shape.Dimension(None)
      self.assertIsNone(dim.value)
      self.assertEqual(dim.value, tensor_shape.Dimension(None).value)
      self.assertEqual(
          tensor_shape.Dimension(None).value,
          (dim + tensor_shape.Dimension(None)).value,
      )
      self.assertEqual(
          tensor_shape.Dimension(None).value,
          (dim * tensor_shape.Dimension(None)).value,
      )
      self.assertEqual(
          tensor_shape.Dimension(None).value,
          (dim // tensor_shape.Dimension(None)).value,
      )
      self.assertEqual(
          tensor_shape.Dimension(None).value,
          dim.merge_with(tensor_shape.Dimension(None)).value,
      )
      self.assertIsNone(
          tensor_shape.Dimension(None) < tensor_shape.Dimension(None)
      )
      self.assertIsNone(
          tensor_shape.Dimension(None) <= tensor_shape.Dimension(None)
      )
      self.assertIsNone(
          tensor_shape.Dimension(None) > tensor_shape.Dimension(None)
      )
      self.assertIsNone(
          tensor_shape.Dimension(None) >= tensor_shape.Dimension(None)
      )
  
imports: from absl.testing import parameterized
  from tensorflow.core.framework import tensor_shape_pb2
  from tensorflow.core.function import trace_type
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import tensor_shape
  from tensorflow.python.framework import test_util
  from tensorflow.python.platform import googletest
label_desc: Use image node_id 2 for calling the DimensionTest obj's underlying member method code with example usage: obj.testUnknownDimension() without return types