print signatures wrong. now rename it to _func

test=document_fix

Author: wadefelix

python/paddle/fluid/layers/ops.py

@@ -87,26 +87,26 @@
     _new_OP = _OP
     if _OP in __deprecated_func_name__:
         _new_OP = __deprecated_func_name__[_OP]
-    func = generate_activation_fn(_OP)
-    func = deprecated(
-        since="2.0.0", update_to="paddle.nn.functional.%s" % (_new_OP))(func)
-    globals()[_OP] = func
+    _func = generate_activation_fn(_OP)
+    _func = deprecated(
+        since="2.0.0", update_to="paddle.nn.functional.%s" % (_new_OP))(_func)
+    globals()[_OP] = _func
 
 for _OP in set(__unary_func__):
     _new_OP = _OP
     if _OP in __deprecated_func_name__:
         _new_OP = __deprecated_func_name__[_OP]
-    func = generate_activation_fn(_OP)
-    func = deprecated(since="2.0.0", update_to="paddle.%s" % (_new_OP))(func)
-    globals()[_OP] = func
+    _func = generate_activation_fn(_OP)
+    _func = deprecated(since="2.0.0", update_to="paddle.%s" % (_new_OP))(_func)
+    globals()[_OP] = _func
 
 for _OP in set(__inplace_unary_func__):
     _new_OP = _OP
     if _OP in __deprecated_func_name__:
         _new_OP = __deprecated_func_name__[_OP]
-    func = generate_inplace_fn(_OP)
-    func = deprecated(since="2.0.0", update_to="paddle.%s" % (_new_OP))(func)
-    globals()[_OP] = func
+    _func = generate_inplace_fn(_OP)
+    _func = deprecated(since="2.0.0", update_to="paddle.%s" % (_new_OP))(_func)
+    globals()[_OP] = _func
 
 add_sample_code(globals()["sigmoid"], r"""
 Examples: