code: def test_label_smoothing(self):
      logits = np.array(((10.0, -10.0, -10.0)))
      y_true = np.array(((1, 0, 1)))
      label_smoothing = 0.1
      bce_obj = metrics.BinaryCrossentropy(
          from_logits=True, label_smoothing=label_smoothing
      )
      result = bce_obj(y_true, logits)
      expected_value = (10.0 + 5.0 * label_smoothing) / 3.0
      self.assertAllClose(expected_value, result, atol=1e-3)
  
imports: import numpy
  from keras import metrics
  from keras import testing
label_desc: Use image node_id 6 for calling the BinaryCrossentropyTest obj's underlying member method code with example usage: obj.test_label_smoothing() without return types