🐛 fix test

    raise NotImplementedError('Featurizer is not defined.')

# callback function for apply_async

# NOTE : apply_async() : nested function is not executed

# https://stackoverflow.com/questions/56533827/pool-apply-async-nested-function-is-not-executed

def _featurize_callback(featurizer, mol_pdb_file, protein_pdb_file, log_message):

  logging.info(log_message)

  return featurizer._featurize(mol_pdb_file, protein_pdb_file)

class ComplexFeaturizer(Featurizer):

  """"

  Abstract class for calculating features for mol/protein complexes.

    failures: list

      Indices of complexes that failed to featurize.

    """

    # callback function for apply_async

    def _featurize_callback(mol_pdb_file, protein_pdb_file, log_message):

      logging.info(log_message)

      return self._featurize(mol_pdb_file, protein_pdb_file)

    pool = multiprocessing.Pool()

    results = []

      log_message = "Featurizing %d / %d" % (i, len(mol_files))

      results.append(

          pool.apply_async(_featurize_callback,

                           (mol_file, protein_pdb, log_message)))

                           (self, mol_file, protein_pdb, log_message)))

    pool.close()

    features = []

    failures = []