old_contents: """
  Making it easy to import in classes.
  """
  from deepchem.feat.base_classes import Featurizer
  from deepchem.feat.base_classes import MolecularFeaturizer
  from deepchem.feat.base_classes import MaterialStructureFeaturizer
  from deepchem.feat.base_classes import MaterialCompositionFeaturizer
  from deepchem.feat.base_classes import ComplexFeaturizer
  from deepchem.feat.base_classes import UserDefinedFeaturizer
  from deepchem.feat.graph_features import ConvMolFeaturizer
  from deepchem.feat.graph_features import WeaveFeaturizer
  from deepchem.feat.fingerprints import CircularFingerprint
  from deepchem.feat.rdkit_descriptors import RDKitDescriptors
  from deepchem.feat.coulomb_matrices import CoulombMatrix
  from deepchem.feat.coulomb_matrices import CoulombMatrixEig
  from deepchem.feat.coulomb_matrices import BPSymmetryFunctionInput
  from deepchem.feat.rdkit_grid_featurizer import RdkitGridFeaturizer
  from deepchem.feat.binding_pocket_features import BindingPocketFeaturizer
  from deepchem.feat.one_hot import OneHotFeaturizer
  from deepchem.feat.raw_featurizer import RawFeaturizer
  from deepchem.feat.atomic_coordinates import AtomicCoordinates
  from deepchem.feat.atomic_coordinates import NeighborListComplexAtomicCoordinates
  from deepchem.feat.adjacency_fingerprints import AdjacencyFingerprint
  from deepchem.feat.smiles_featurizers import SmilesToSeq, SmilesToImage
  from deepchem.feat.material_featurizers import ElementPropertyFingerprint
  from deepchem.feat.material_featurizers import SineCoulombMatrix
  from deepchem.feat.material_featurizers import CGCNNFeaturizer
  
  try:
    import transformers
    from transformers import BertTokenizer
  
    from deepchem.feat.smiles_tokenizer import SmilesTokenizer
    from deepchem.feat.smiles_tokenizer import BasicSmilesTokenizer
  except ImportError:
    logger.warning(
        "HuggingFace transformers is not available. Please install using 'pip install transformers' to use the SmilesTokenizer")
  
new_contents: """
  Making it easy to import in classes.
  """
  from deepchem.feat.base_classes import Featurizer
  from deepchem.feat.base_classes import MolecularFeaturizer
  from deepchem.feat.base_classes import MaterialStructureFeaturizer
  from deepchem.feat.base_classes import MaterialCompositionFeaturizer
  from deepchem.feat.base_classes import ComplexFeaturizer
  from deepchem.feat.base_classes import UserDefinedFeaturizer
  from deepchem.feat.graph_features import ConvMolFeaturizer
  from deepchem.feat.graph_features import WeaveFeaturizer
  from deepchem.feat.fingerprints import CircularFingerprint
  from deepchem.feat.rdkit_descriptors import RDKitDescriptors
  from deepchem.feat.coulomb_matrices import CoulombMatrix
  from deepchem.feat.coulomb_matrices import CoulombMatrixEig
  from deepchem.feat.coulomb_matrices import BPSymmetryFunctionInput
  from deepchem.feat.rdkit_grid_featurizer import RdkitGridFeaturizer
  from deepchem.feat.binding_pocket_features import BindingPocketFeaturizer
  from deepchem.feat.one_hot import OneHotFeaturizer
  from deepchem.feat.raw_featurizer import RawFeaturizer
  from deepchem.feat.atomic_coordinates import AtomicCoordinates
  from deepchem.feat.atomic_coordinates import NeighborListComplexAtomicCoordinates
  from deepchem.feat.adjacency_fingerprints import AdjacencyFingerprint
  from deepchem.feat.smiles_featurizers import SmilesToSeq, SmilesToImage
  from deepchem.feat.material_featurizers import ElementPropertyFingerprint
  from deepchem.feat.material_featurizers import SineCoulombMatrix
  from deepchem.feat.material_featurizers import CGCNNFeaturizer
  
  try:
    import transformers
    from transformers import BertTokenizer
  
    from deepchem.feat.smiles_tokenizer import SmilesTokenizer
    from deepchem.feat.smiles_tokenizer import BasicSmilesTokenizer
  except ModuleNotFoundError:
    logger.warning(
        "HuggingFace transformers is not available. Please install using 'pip install transformers' to use the SmilesTokenizer")
  
subject: change from import to modulenotfounderror