modify init

ppcls/arch/backbone/__init__.py

@@ -38,6 +38,7 @@ from .model_zoo.dpn import DPN68, DPN92, DPN98, DPN107, DPN131
 from .model_zoo.dsnet import DSNet_tiny, DSNet_small, DSNet_base
 from .model_zoo.densenet import DenseNet121, DenseNet161, DenseNet169, DenseNet201, DenseNet264
 from .model_zoo.efficientnet import EfficientNetB0, EfficientNetB1, EfficientNetB2, EfficientNetB3, EfficientNetB4, EfficientNetB5, EfficientNetB6, EfficientNetB7, EfficientNetB0_small
+from .model_zoo.efficientnet_v2 import EfficientNetV2_S
 from .model_zoo.resnest import ResNeSt50_fast_1s1x64d, ResNeSt50, ResNeSt101, ResNeSt200, ResNeSt269
 from .model_zoo.googlenet import GoogLeNet
 from .model_zoo.mobilenet_v2 import MobileNetV2_x0_25, MobileNetV2_x0_5, MobileNetV2_x0_75, MobileNetV2, MobileNetV2_x1_5, MobileNetV2_x2_0