code: def __init__(
      self,
      backend,
      initial_lr,
      warmup_epochs=5,
      momentum_correction=True,
      steps_per_epoch=None,
      verbose=0,
      *args,
  ):
      def multiplier(epoch):
          # Adjust epoch to produce round numbers at the end of each epoch, so that TensorBoard
          # learning rate graphs look better.
          epoch += 1.0 / self.steps_per_epoch
          return (
              1.0
              / hvd.size()
              * (epoch * (hvd.size() - 1) / warmup_epochs + 1)
          )
  
      super(LearningRateWarmupCallbackImpl, self).__init__(
          backend,
          initial_lr,
          multiplier,
          start_epoch=0,
          end_epoch=warmup_epochs,
          staircase=False,
          momentum_correction=momentum_correction,
          steps_per_epoch=steps_per_epoch,
          *args,
      )
      self.verbose = verbose
  
imports: from packaging import version
  import warnings
  import horovod.tensorflow
  import tensorflow
label_desc: Use image node_id 1 to create a new LearningRateWarmupCallbackImpl object from inherited base classes: LearningRateScheduleCallbackImpl with example: obj = LearningRateWarmupCallbackImpl(backend, initial_lr, warmup_epochs, momentum_correction, steps_per_epoch, verbose)