docstr: Gets called at the beginning of ``evaluate()``
  
  Default implementation loads the best-performing checkpoint for
  evaluation, based on stored metrics.
  
  Arguments
  ---------
  max_key : str
      Key to use for finding best checkpoint (higher is better).
      By default, passed to ``self.checkpointer.recover_if_possible()``.
  min_key : str
      Key to use for finding best checkpoint (lower is better).
      By default, passed to ``self.checkpointer.recover_if_possible()``.
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code: def on_evaluate_start(self, max_key=None, min_key=None):
      """Gets called at the beginning of ``evaluate()``
  
      Default implementation loads the best-performing checkpoint for
      evaluation, based on stored metrics.
  
      Arguments
      ---------
      max_key : str
          Key to use for finding best checkpoint (higher is better).
          By default, passed to ``self.checkpointer.recover_if_possible()``.
      min_key : str
          Key to use for finding best checkpoint (lower is better).
          By default, passed to ``self.checkpointer.recover_if_possible()``.
      """
      self._recover_checkpoint(min_key, max_key)
  
imports: from speechbrain.dataio.dataset import FilteredSortedDynamicItemDataset, DynamicItemDataset
  from speechbrain.dataio.sampler import BalancingDataSampler
  from speechbrain.utils.data_utils import undo_padding
  import datasets
  import logging
  import os
  import random
  import speechbrain
  import sys
  from enum import Enum
  from collections import namedtuple
  from hyperpyyaml import load_hyperpyyaml
  from functools import partial
  from speechbrain.utils.distributed import run_on_main
  from speechbrain.utils.pretrained import save_for_pretrained
  from speechbrain.lobes.models.g2p.dataio import enable_eos_bos, grapheme_pipeline, phoneme_pipeline, tokenizer_encode_pipeline, add_bos_eos, get_sequence_key, phonemes_to_label
  from speechbrain.dataio.wer import print_alignments
  from speechbrain.wordemb.util import expand_to_chars
  from io import StringIO
  from speechbrain.utils import hpopt
  import numpy
label_desc: Use image node_id 3 for calling the G2PBrain obj's underlying member method code with example usage: obj.on_evaluate_start(max_key, min_key) without return types