code: def _test_unary_op_method(self, mock_method, operator):
      mock_tensor = Mock()
      mock_method.return_value = mock_tensor
      x = keras_tensor.KerasTensor(shape=(3, 4), dtype="float32")
      result = operator(x)
      mock_method.assert_called_once_with(x)
      self.assertEqual(result, mock_tensor)
  
imports: from unittest.mock import Mock
  from unittest.mock import patch
  import numpy
  import tensorflow
  from keras import backend
  from keras import ops
  from keras import testing
  from keras.backend.common import keras_tensor
label_desc: Use image node_id 20 for calling the KerasTensorTest obj's underlying member method code with example usage: obj._test_unary_op_method(mock_method, operator) without return types