code: def _train(
      self,
      sub_train,
      sub_valid,
      weights,
      early_stopping,
      model_selection,
      optimizer,
      scheduler,
      tmp_dir,
  ):
      stop = False
      for epoch in range(0, self.num_epochs):
          if not stop:
              start_time = datetime.datetime.now()
  
              (
                  train_acc,
                  train_loss,
                  valid_acc,
                  valid_loss,
                  stop,
              ) = self._train_loop_epoch(
                  epoch,
                  sub_train,
                  sub_valid,
                  weights,
                  early_stopping,
                  model_selection,
                  optimizer,
                  scheduler,
                  tmp_dir,
              )
  
              timedelta = datetime.datetime.now() - start_time
  
              self._log_epoch(
                  epoch,
                  timedelta,
                  sub_train,
                  sub_valid,
                  train_acc,
                  train_loss,
                  valid_acc,
                  valid_loss,
              )
  
imports: import datetime
  import logging
  import tempfile
  import warnings
  import numpy
  from functools import partial
  from small_text.classifiers.classification import EmbeddingMixin
  from small_text.integrations.pytorch.exceptions import PytorchNotFoundError
  from small_text.utils.classification import get_splits
  from small_text.utils.context import build_pbar_context
  from small_text.utils.data import check_training_data, list_length
  from small_text.utils.datetime import format_timedelta
  from small_text.utils.annotations import early_stopping_deprecation_warning, model_selection_deprecation_warning
  from small_text.utils.labels import get_num_labels
  from small_text.utils.logging import verbosity_logger, VERBOSITY_MORE_VERBOSE
  from small_text.utils.system import get_tmp_dir_base
label_desc: Use image node_id 6 for calling the TransformerBasedClassification obj's underlying member method code with example usage: obj._train(sub_train, sub_valid, weights, early_stopping, model_selection, optimizer, scheduler, tmp_dir) without return types