class_docstr: A speaker model with ResNet layers. 
class_docstr_tok: ["A","speaker","model","with","ResNet","layers","."]
code: def bn_layer(self, x, bn_name):
      x = tf.layers.batch_normalization(
          x, axis=-1, momentum=0.9, training=self.train, name=bn_name
      )
      return x
  
imports: import math
  from absl import logging
  import delta.compat
  import tensorflow.keras.layers
  from delta import utils
  from delta.layers import common_layers
  from delta.models.base_model import RawModel
  from delta.utils.register import registers
  from delta.utils.loss.loss_utils import arcface_loss
  from delta.utils.hparam import HParams
label_desc: Use image node_id 3 for calling the SpeakerResNetRawModel obj's underlying member method code with example usage: obj.bn_layer(x, bn_name) and returns: x