Update `add` `clip` `MSELoss` and `no_grad` (#28530)

also fix `no_grad` alias

python/paddle/__init__.py

@@ -263,7 +263,6 @@ from .device import XPUPlace
 from .fluid.dygraph.base import enable_dygraph as disable_static  #DEFINE_ALIAS
 from .fluid.dygraph.base import disable_dygraph as enable_static  #DEFINE_ALIAS
 from .fluid.framework import in_dygraph_mode as in_dynamic_mode  #DEFINE_ALIAS
-from .fluid.dygraph.base import no_grad_ as no_grad  #DEFINE_ALIAS
 from .fluid.layers import crop_tensor as crop  #DEFINE_ALIAS
 
 from . import jit

python/paddle/fluid/dygraph/base.py

@@ -272,8 +272,6 @@ class no_grad_:
         import numpy as np
         import paddle
 
-        paddle.disable_static()
-
         # use as generator
 
         data = np.array([[2, 3], [4, 5]]).astype('float32')

python/paddle/framework/__init__.py

@@ -38,7 +38,7 @@ from ..fluid.core import CUDAPinnedPlace  #DEFINE_ALIAS
 from ..fluid.core import VarBase  #DEFINE_ALIAS
 
 from paddle.fluid import core  #DEFINE_ALIAS
-from ..fluid.dygraph.base import no_grad  #DEFINE_ALIAS
+from ..fluid.dygraph.base import no_grad_ as no_grad  #DEFINE_ALIAS
 from ..fluid.dygraph.base import to_variable  #DEFINE_ALIAS
 from ..fluid.dygraph.base import grad  #DEFINE_ALIAS
 from .io import save

python/paddle/nn/layer/loss.py

@@ -418,12 +418,11 @@ class MSELoss(fluid.dygraph.layers.Layer):
             input_data = np.array([1.5]).astype("float32")
             label_data = np.array([1.7]).astype("float32")
 
-            paddle.disable_static()
             mse_loss = paddle.nn.loss.MSELoss()
             input = paddle.to_tensor(input_data)
             label = paddle.to_tensor(label_data)
             output = mse_loss(input, label)
-            print(output.numpy())
+            print(output)
             # [0.04000002]
     """
 

python/paddle/tensor/math.py

@@ -274,18 +274,15 @@ def _elementwise_op(helper):
 
 def add(x, y, name=None):
     """
-Examples:
+    Examples:
 
     ..  code-block:: python
 
         import paddle
-
-        paddle.disable_static()
         x = paddle.to_tensor([2, 3, 4], 'float64')
         y = paddle.to_tensor([1, 5, 2], 'float64')
         z = paddle.add(x, y)
-        np_z = z.numpy()
-        print(np_z)  # [3., 8., 6. ]
+        print(z)  # [3., 8., 6. ]
 
     """
     op_type = 'elementwise_add'
@@ -1411,9 +1408,6 @@ def addcmul(input, tensor1, tensor2, value=1.0, name=None):
 
 def clip(x, min=None, max=None, name=None):
     """
-        :alias_main: paddle.clip
-        :alias: paddle.clip,paddle.tensor.clip,paddle.tensor.math.clip
-
     **clip layer**
 
     This operator clip all elements in input into the range [ min, max ] and return
@@ -1440,15 +1434,13 @@ def clip(x, min=None, max=None, name=None):
         .. code-block:: python
 
             import paddle
-
-            paddle.disable_static()
             x1 = paddle.to_tensor([[1.2, 3.5], [4.5, 6.4]], 'float32')
             out1 = paddle.clip(x1, min=3.5, max=5.0)
             out2 = paddle.clip(x1, min=2.5)
-            print(out1.numpy())
+            print(out1)
             # [[3.5, 3.5]
             # [4.5, 5.0]]
-            print(out2.numpy())
+            print(out2)
             # [[2.5, 3.5]
             # [[4.5, 6.4]
     """