[Cherry-pick]Delete the function of saving layer object. (#34039)

* Save all the information of 'ParamBase' in 'Layer'. (#33500)

* Save all the information of 'ParamBase' in 'Layer'.

* edit unittest

* delete the function of saving layer object. (#33697)

* delete the function of saving layer object.

* edit doc of paddle.save/load and polish error message

Author: hbwx24

python/paddle/fluid/tests/unittests/test_paddle_save_load.py

@@ -869,21 +869,11 @@ def test_save_load_layer(self):
         layer2 = LinearNet()
         layer1.eval()
         layer2.eval()
+        origin_layer = (layer1, layer2)
         origin = (layer1(inps), layer2(inps))
         path = "test_save_load_layer_/layer.pdmodel"
-        paddle.save((layer1, layer2), path)
-
-        # static
-        paddle.enable_static()
         with self.assertRaises(ValueError):
-            paddle.load(path)
-        # dygraph
-        paddle.disable_static()
-
-        loaded_layer = paddle.load(path)
-        loaded_result = [l(inps) for l in loaded_layer]
-        for i in range(len(origin)):
-            self.assertTrue((origin[i] - loaded_result[i]).abs().max() < 1e-10)
+            paddle.save(origin_layer, path)
 
 
 if __name__ == '__main__':

python/paddle/framework/io.py

@@ -232,7 +232,7 @@ def _pickle_save(obj, f, protocol):
         raise ValueError("Expected 1<'protocol'<5, but received protocol={}".
                          format(protocol))
 
-    def reudce_varbase(self):
+    def reduce_varbase(self):
         data = self.numpy()
         name = self.name
 
@@ -243,16 +243,32 @@ def reduce_LoDTensor(self):
 
         return (eval, ('data', {'data': data}))
 
+    def reduce_Layer(self):
+        raise ValueError(
+            "paddle do not support saving `paddle.nn.Layer` object.")
+
+    dispatch_table_layer = dict()
+
+    def create_layer_dispatch_table(layer):
+        dispatch_table_layer[layer.__class__] = reduce_Layer
+        return layer
+
+    _parse_every_object(obj, lambda v: isinstance(v, core.Layer),
+                        create_layer_dispatch_table)
+
     def add_dispatch_table():
         # This is not a good method, because the pickle module has been modified.
-        pickle.dispatch_table[core.VarBase] = reudce_varbase
-        pickle.dispatch_table[ParamBase] = reudce_varbase
+        pickle.dispatch_table[core.VarBase] = reduce_varbase
+        pickle.dispatch_table[ParamBase] = reduce_varbase
         pickle.dispatch_table[core.LoDTensor] = reduce_LoDTensor
+        pickle.dispatch_table.update(dispatch_table_layer)
 
     def pop_dispatch_table():
         pickle.dispatch_table.pop(core.VarBase)
         pickle.dispatch_table.pop(core.LoDTensor)
         pickle.dispatch_table.pop(ParamBase)
+        for k in dispatch_table_layer:
+            pickle.dispatch_table.pop(k)
 
     # When value of dict is lager than 4GB ,there is a Bug on 'MAC python3'
     if sys.platform == 'darwin' and sys.version_info.major == 3:
@@ -272,10 +288,10 @@ def pop_dispatch_table():
             pickler = pickle.Pickler(f, protocol)
             pickler.dispatch_table = copyreg.dispatch_table.copy()
 
-            pickler.dispatch_table[core.VarBase] = reudce_varbase
+            pickler.dispatch_table[core.VarBase] = reduce_varbase
             pickler.dispatch_table[core.LoDTensor] = reduce_LoDTensor
-            pickler.dispatch_table[ParamBase] = reudce_varbase
-
+            pickler.dispatch_table[ParamBase] = reduce_varbase
+            pickler.dispatch_table.update(dispatch_table_layer)
             pickler.dump(obj)
 
 
@@ -496,7 +512,7 @@ def save(obj, path, protocol=4, **configs):
     Save an object to the specified path.
     
     .. note::
-        Now supports saving ``state_dict`` of Layer/Optimizer, Layer, Tensor and nested structure containing Tensor, Program.
+        Now supports saving ``state_dict`` of Layer/Optimizer, Tensor and nested structure containing Tensor, Program.
 
     .. note::
         Different from ``paddle.jit.save``, since the save result of ``paddle.save`` is a single file, 
@@ -690,7 +706,7 @@ def load(path, **configs):
     Load an object can be used in paddle from specified path.
 
     .. note::
-        Now supports loading ``state_dict`` of Layer/Optimizer, Layer, Tensor and nested structure containing Tensor, Program.
+        Now supports loading ``state_dict`` of Layer/Optimizer, Tensor and nested structure containing Tensor, Program.
 
     .. note::
         In order to use the model parameters saved by paddle more efficiently,