code: def l2_norm(self, x, axis):
      epsilon = 1e-12
      square_sum = np.sum(np.square(x), axis=axis, keepdims=True)
      x_inv_norm = 1 / np.sqrt(np.maximum(square_sum, epsilon))
      return np.multiply(x, x_inv_norm)
  
imports: import numpy
  from absl.testing import parameterized
  from keras import testing
  from keras.metrics import regression_metrics
label_desc: Use image node_id 1 for calling the CosineSimilarityTest obj's underlying member method code with example usage: obj.l2_norm(x, axis) and returns: np