code: def _bias_add(x, b, data_format):
      
      if data_format == 'NHWC':
          return tf.add(x, b)
      elif data_format == 'NCHW':
          return tf.add(x, _to_channel_first_bias(b))
      else:
          raise ValueError('invalid data_format: %s' % data_format)
docs: Alternative implementation of tf.nn.bias_add which is compatiable with tensorRT.