Simplify name

No need to point out ng anymore

src/attr/_make.py

@@ -50,7 +50,7 @@
 # Unique object for unequivocal getattr() defaults.
 _sentinel = object()
 
-_ng_default_on_setattr = setters.pipe(setters.convert, setters.validate)
+_default_on_setattr = setters.pipe(setters.convert, setters.validate)
 
 
 class _Nothing(enum.Enum):
@@ -766,7 +766,7 @@ def __init__(
 
             self._wrote_own_setattr = True
         elif on_setattr in (
-            _ng_default_on_setattr,
+            _default_on_setattr,
             setters.validate,
             setters.convert,
         ):
@@ -781,7 +781,7 @@ def __init__(
                     break
             if (
                 (
-                    on_setattr == _ng_default_on_setattr
+                    on_setattr == _default_on_setattr
                     and not (has_validator or has_converter)
                 )
                 or (on_setattr == setters.validate and not has_validator)

src/attr/_next_gen.py

@@ -13,8 +13,8 @@
 from ._funcs import astuple as _astuple
 from ._make import (
     NOTHING,
+    _default_on_setattr,
     _frozen_setattrs,
-    _ng_default_on_setattr,
     attrib,
     attrs,
 )
@@ -124,7 +124,7 @@ def wrap(cls):
 
         # By default, mutable classes convert & validate on setattr.
         if frozen is False and on_setattr is None:
-            on_setattr = _ng_default_on_setattr
+            on_setattr = _default_on_setattr
 
         # However, if we subclass a frozen class, we inherit the immutability
         # and disable on_setattr.