add import PrecipNet in ppsci/arch/__init__.py

Author: zhiminzhang0830

ppsci/arch/__init__.py

@@ -21,6 +21,7 @@
 from ppsci.arch.physx_transformer import PhysformerGPT2  # isort:skip
 from ppsci.arch.model_list import ModelList  # isort:skip
 from ppsci.arch.afno import AFNONet  # isort:skip
+from ppsci.arch.afno import PrecipNet  # isort:skip
 from ppsci.utils import logger  # isort:skip
 
 
@@ -32,6 +33,7 @@
     "PhysformerGPT2",
     "ModelList",
     "AFNONet",
+    "PrecipNet",
     "build_model",
 ]