code: def _default_callbacks(self):
      return [
          ("epoch_timer", EpochTimer()),
          (
              "train_loss",
              PassthroughScoring(
                  name="train_loss",
                  on_train=True,
              ),
          ),
          (
              "valid_loss",
              PassthroughScoring(
                  name="valid_loss",
              ),
          ),
          # add train accuracy because by default, there is no valid split
          (
              "train_acc",
              EpochScoring(
                  "accuracy",
                  name="train_acc",
                  lower_is_better=False,
                  on_train=True,
              ),
          ),
          (
              "valid_acc",
              EpochScoring(
                  "accuracy",
                  name="valid_acc",
                  lower_is_better=False,
              ),
          ),
          ("print_log", PrintLog()),
      ]
  
imports: import pickle
  import re
  import gpytorch
  import numpy
  import torch
  from skorch.net import NeuralNet
  from skorch.dataset import ValidSplit
  from skorch.dataset import unpack_data
  from skorch.callbacks import EpochScoring
  from skorch.callbacks import EpochTimer
  from skorch.callbacks import PassthroughScoring
  from skorch.callbacks import PrintLog
  from skorch.utils import check_is_fitted
  from skorch.utils import get_dim
  from skorch.utils import is_dataset
  from skorch.utils import to_numpy
  from skorch.utils import to_tensor
label_desc: Use image node_id 2 for calling the GPBinaryClassifier obj's underlying member method code with example usage: obj._default_callbacks() and returns: list