Update __init__.py

paddlers/models/ppgan/apps/__init__.py

@@ -13,4 +13,5 @@
 # limitations under the License.
 
 from .realsr_predictor import RealSRPredictor
-from .mpr_predictor import MPRPredictor
+from .mpr_predictor import MPRPredictor
+from .drn_predictor import DRNPredictor