docstr: At the end of the optimizer step, apply noam annealing.
docstr_tok: ["At","the","end","of","the","optimizer","step",",","apply","noam","annealing","."]
code: def on_fit_batch_end(self, batch, outputs, loss, should_step):
      """At the end of the optimizer step, apply noam annealing."""
      if should_step:
          self.hparams.noam_annealing(self.optimizer)
  
imports: import os
  import sys
  import torch
  import logging
  import torchaudio
  import numpy
  import speechbrain
  from speechbrain.inference.vocoders import HIFIGAN
  from pathlib import Path
  from hyperpyyaml import load_hyperpyyaml
  from speechbrain.utils.data_utils import scalarize
  from speechbrain.inference.text import GraphemeToPhoneme
label_desc: Use image node_id 3 for calling the FastSpeech2Brain obj's underlying member method code with example usage: obj.on_fit_batch_end(batch, outputs, loss, should_step) without return types