code: def _get_default_sample_split(sample_split, prediction_model, is_ppm):
      if sample_split == "auto":
          sample_split = "oob"
          if is_ppm:
              if prediction_model.loo:
                  sample_split = "loo"
      return sample_split
  
imports: import numpy
  import pandas
  from scipy.spatial.distance import pdist
  from functools import partial
  from .ppms import PartialPredictionModelBase, GenericRegressorPPM, GenericClassifierPPM
  from .block_transformers import _blocked_train_test_split
  from .ranking_stability import tauAP_b, rbo
label_desc: Use image node_id 2 for calling a global function with example usage: _get_default_sample_split(sample_split, prediction_model, is_ppm) and returns: sample_split