bpo-40792: Make the result of PyNumber_Index() always having exact type int. (GH-20443)
Previously, the result could have been an instance of a subclass of int.
Also revert bpo-26202 and make attributes start, stop and step of the range
object having exact type int.
Add private function _PyNumber_Index() which preserves the old behavior
of PyNumber_Index() for performance to use it in the conversion functions
like PyLong_AsLong().
diff --git a/Doc/library/operator.rst b/Doc/library/operator.rst
index fa02bde..36c5355 100644
--- a/Doc/library/operator.rst
+++ b/Doc/library/operator.rst
@@ -112,6 +112,10 @@
Return *a* converted to an integer. Equivalent to ``a.__index__()``.
+ .. versionchanged:: 3.10
+ The result always has exact type :class:`int`. Previously, the result
+ could have been an instance of a subclass of ``int``.
+
.. function:: inv(obj)
invert(obj)