Update default values for ast.ImportFrom initialization

stdlib/@tests/stubtest_allowlists/common.txt

@@ -208,11 +208,8 @@ _?ast.excepthandler.__init__
 _?ast.expr.__init__
 _?ast.stmt.__init__
 
-_ast.ImportFrom.level  # None on the class, but never None on instances
-
 argparse.Namespace.__setattr__  # should allow setting any attribute
 
-ast.ImportFrom.level  # None on the class, but never None on instances
 ast.NodeVisitor.visit_\w+  # Methods are discovered dynamically, see #3796
 _?asyncio.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future.__init__  # Usually initialized from c object

stdlib/@tests/stubtest_allowlists/py39.txt

@@ -1,6 +1,8 @@
 # ========
 # 3.9 only
 # ========
+_ast.ImportFrom.level  # None on the class, but never None on instances
+ast.ImportFrom.level  # None on the class, but never None on instances
 
 # Exists at runtime, but missing from stubs
 collections.AsyncIterable.__class_getitem__

stdlib/ast.pyi

@@ -735,13 +735,27 @@ class ImportFrom(stmt):
         __match_args__ = ("module", "names", "level")
     module: str | None
     names: list[alias]
-    level: int
+    if sys.version_info >= (3, 10):
+        level: int | None
+    else:
+        level: int
     if sys.version_info >= (3, 13):
         @overload
-        def __init__(self, module: str | None, names: list[alias], level: int, **kwargs: Unpack[_Attributes]) -> None: ...
+        def __init__(
+            self, module: None = None, names: list[alias] = ..., *, level: int | None = None, **kwargs: Unpack[_Attributes]
+        ) -> None: ...
+        @overload
+        def __init__(
+            self, module: str | None = None, *, names: list[alias] = ..., level: int | None = None, **kwargs: Unpack[_Attributes]
+        ) -> None: ...
+    elif sys.version_info >= (3, 10):
+        @overload
+        def __init__(
+            self, module: str | None, names: list[alias], level: int | None = None, **kwargs: Unpack[_Attributes]
+        ) -> None: ...
         @overload
         def __init__(
-            self, module: str | None = None, names: list[alias] = ..., *, level: int, **kwargs: Unpack[_Attributes]
+            self, module: str | None = None, *, names: list[alias], level: int | None = None, **kwargs: Unpack[_Attributes]
         ) -> None: ...
     else:
         @overload
@@ -753,7 +767,7 @@ class ImportFrom(stmt):
 
     if sys.version_info >= (3, 14):
         def __replace__(
-            self, *, module: str | None = ..., names: list[alias] = ..., level: int = ..., **kwargs: Unpack[_Attributes]
+            self, *, module: str | None = ..., names: list[alias] = ..., level: int | None = ..., **kwargs: Unpack[_Attributes]
         ) -> Self: ...
 
 class Global(stmt):