code: def test_binary_cross_entropy_loss(self):
      # TODO(jonni): Clarify desired semantics/naming, then test it.
      layer = tl.BinaryCrossEntropyLoss()
      xs = [np.ones((9, 1)), np.ones((9, 1)), np.ones((9, 1))]
      y = layer(xs)
      self.assertEqual(y.shape, ())
  
imports: from absl.testing import absltest
  import numpy
  import trax.layers
label_desc: Use image node_id 15 for calling the MetricsTest obj's underlying member method code with example usage: obj.test_binary_cross_entropy_loss() without return types