code: def test_input_fully_masked(self, synchronized):
      norm = layers.BatchNormalization(
          scale=False,
          center=False,
          synchronized=synchronized,
      )
      x = np.zeros((4, 5))
      mask = np.zeros((4,), dtype=np.float32)
      y = norm(x, mask=mask, training=True)
      self.assertAllClose(y, np.zeros_like(x, dtype=np.float32))
  
file_path: keras/keras/layers/normalization/batch_normalization_test.py
imports: import numpy
  import pytest
  from absl.testing import parameterized
  from keras import backend
  from keras import layers
  from keras import testing
  from keras.losses import MeanSquaredError
  from keras.models import Model
label_desc: Use image node_id 3 for calling the BatchNormalizationTest obj's underlying member method code with example usage: obj.test_input_fully_masked(synchronized) without return types