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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def batch_norm(inputs, training, data_format):
 """Performs a batch normalization using a standard set of parameters."""

  # We set fused=True for a significant performance boost. See
  # https://www.tensorflow.org/performance/performance_guide#common_fused_ops
  outputs = tf.layers.batch_normalization(
      inputs=inputs, axis=1 if data_format == 'channels_first' else 3,
      momentum=_BATCH_NORM_DECAY, epsilon=_BATCH_NORM_EPSILON, center=True,
      scale=True, training=training, fused=True)

  resnet_log_helper.log_batch_norm(
      input_tensor=inputs, output_tensor=outputs, momentum=_BATCH_NORM_DECAY,
      epsilon=_BATCH_NORM_EPSILON, center=True, scale=True, training=training)

  return outputs