Add documentation for sys._jit_enabled and what's new entry.

Author: Eclips4

Doc/library/sys.rst

@@ -1235,6 +1235,13 @@ always available.
 
    .. versionadded:: 3.13
 
+.. function:: _jit_enabled()
+   Return :const:`True` if :ref:`JIT compiler <whatsnew313-jit-compiler>` is active.
+   Return :const:`False` otherwise.
+
+   .. availability:: JIT builds, tier 2 interpreter doesn't count here.
+
+   .. versionadded:: next
 
 .. function:: is_finalizing()
 

Doc/whatsnew/3.14.rst

@@ -443,6 +443,9 @@ sys
   which only exists in specialized builds of Python, may now return objects
   from other interpreters than the one it's called in.
 
+* Add a :func:`sys._jit_enabled` which helps to determine in runtime if
+  :ref:`JIT compiler <whatsnew313-jit-compiler>` is active.
+
 
 unicodedata
 -----------

Misc/NEWS.d/next/Core_and_Builtins/2024-11-10-04-59-43.gh-issue-126204.ASKDL1.rst

@@ -1 +1 @@
-Allow to determine whether the JIT is enabled at runtime via :func:`!sys._jit_enabled`.
+Allow to determine whether the JIT is enabled at runtime via :func:`sys._jit_enabled`.