class_docstr: Test some basic splitters.
docstr: Test singletask ButinaSplitter class.
code: def test_singletask_butina_split(self):
      """
      Test singletask ButinaSplitter class.
      """
      solubility_dataset = load_butina_data()
      butina_splitter = dc.splits.ButinaSplitter()
      (
          train_data,
          valid_data,
          test_data,
      ) = butina_splitter.train_valid_test_split(solubility_dataset)
      assert len(train_data) == 8
      assert len(valid_data) == 1
      assert len(test_data) == 1
  
imports: import os
  import unittest
  import numpy
  import deepchem
  from deepchem.data import NumpyDataset
  from deepchem.splits import IndexSplitter
label_desc: Use image node_id 8 for calling the TestSplitter obj's underlying member method code with example usage: obj.test_singletask_butina_split() without return types