fixed issue with importing WGAN

from deepchem.models.robust_multitask import RobustMultitaskRegressor

from deepchem.models.progressive_multitask import ProgressiveMultitaskRegressor, ProgressiveMultitaskClassifier

from deepchem.models.graph_models import WeaveModel, DTNNModel, DAGModel, GraphConvModel, MPNNModel

from deepchem.models.molgan import BasicMolGANModel

from deepchem.models.scscore import ScScoreModel

from deepchem.models.seqtoseq import SeqToSeq

from deepchem.models.gan import GAN, WGAN

from deepchem.models.molgan import BasicMolGANModel

from deepchem.models.cnn import CNN

from deepchem.models.text_cnn import TextCNNModel

from deepchem.models.atomic_conv import AtomicConvModel