def METHOD_NAME(self):
    """
    Test one hot encoding with max_length.
    """
    from rdkit import Chem
    length = len(ZINC_CHARSET) + 1
    smiles = 'CC(=O)Oc1ccccc1C(=O)O'
    mol = Chem.MolFromSmiles(smiles)
    featurizer = OneHotFeaturizer(max_length=120)
    feature = featurizer([mol])
    assert feature.shape == (1, 120, length)
    # untranform
    undo_smiles = featurizer.untransform(feature[0])
    assert smiles == undo_smiles