docstr: Test freesolv sample dataset on MolGraphConvFeaturizer.
  It contains 5 molecule smiles, out of which 3 can be featurized and 2 cannot be featurized.
docstr_tok: ["Test","freesolv","sample","dataset","on","MolGraphConvFeaturizer",".","It","contains","5","molecule","smiles",",","out","of","which","3","can","be","featurized","and","2","can","not","be","featurized","."]
code: def test_featurizer_freesolv(self):
      """
      Test freesolv sample dataset on MolGraphConvFeaturizer.
      It contains 5 molecule smiles, out of which 3 can be featurized and 2 cannot be featurized.
      """
  
      # load sample dataset
      dir = os.path.dirname(os.path.abspath(__file__))
      input_file = os.path.join(
          dir, "data/freesolv_imperfect_sample.csv"
      )
      loader = dc.data.CSVLoader(
          tasks=["y"],
          feature_field="smiles",
          featurizer=MolGraphConvFeaturizer(),
      )
      dataset = loader.create_dataset(input_file)
      assert len(pd.read_csv(input_file)) == 5
      assert len(dataset) == 3
      assert isinstance(dataset.X[0], dc.feat.GraphData)
  
file_path: deepchem/deepchem/feat/tests/test_mol_graph_conv_featurizer.py
imports: import os
  import unittest
  import numpy
  import pandas
  import deepchem
  from deepchem.feat import MolGraphConvFeaturizer
  from deepchem.feat import PagtnMolGraphFeaturizer
label_desc: Use image node_id 6 for calling the TestMolGraphConvFeaturizer obj's underlying member method code with example usage: obj.test_featurizer_freesolv() without return types