Merge branch 'develop' of github.com:PaddlePaddle/GraphNet into develop

Author: lixinqi

docs/README_contribute.md

@@ -49,7 +49,7 @@ import graph_net
 model = ...  
 
 # Extract your own model
-model = graph_net.torch.extract(name="model_name", dynamic="True")(model)
+model = graph_net.torch.extract(name="model_name", dynamic=True)(model)
 ```
 
 After running, the extracted graph will be saved to: `$GRAPH_NET_EXTRACT_WORKSPACE/model_name/`.

graph_net/__init__.py

@@ -1 +1,21 @@
+__all__ = ["torch", "paddle"]
 
+from importlib import import_module
+from typing import TYPE_CHECKING, Any, List
+
+
+def __getattr__(name: str) -> Any:
+    if name in __all__:
+        module = import_module(f"{__name__}.{name}")
+        globals()[name] = module
+        return module
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
+
+
+def __dir__() -> List[str]:
+    return sorted(list(globals().keys()) + __all__)
+
+
+if TYPE_CHECKING:
+    from . import torch as torch  # type: ignore
+    from . import paddle as paddle  # type: ignore