Suggest use of "hasattr" with checking for 3.13 Expat API availability

Author: hartwork

Doc/library/pyexpat.rst

@@ -217,6 +217,12 @@ XMLParser Objects
    Calling ``SetReparseDeferralEnabled(True)`` allows re-enabling reparse
    deferral.
 
+   Note that :meth:`SetReparseDeferralEnabled` has been backported to prior
+   releases of CPython, so it is recommended to check for availability of
+   :meth:`SetReparseDeferralEnabled` using :func:`hasattr`
+   (rather than inspecting :const:`xml.parsers.expat.version_info`),
+   at runtime.
+
    .. versionadded:: 3.13
 
 .. method:: xmlparser.GetReparseDeferralEnabled()

Doc/library/xml.etree.elementtree.rst

@@ -1402,6 +1402,12 @@ XMLParser Objects
       Disabling reparse deferral has security consequences; please see
       :meth:`xml.parsers.expat.xmlparser.SetReparseDeferralEnabled` for details.
 
+      Note that :meth:`flush` has been backported to prior releases of CPython,
+      so it is recommended to check for availability of :meth:`flush`
+      using :func:`hasattr`
+      (rather than inspecting :const:`xml.parsers.expat.version_info`),
+      at runtime.
+
       .. versionadded:: 3.13
 
 
@@ -1475,6 +1481,12 @@ XMLPullParser Objects
       Disabling reparse deferral has security consequences; please see
       :meth:`xml.parsers.expat.xmlparser.SetReparseDeferralEnabled` for details.
 
+      Note that :meth:`flush` has been backported to prior releases of CPython,
+      so it is recommended to check for availability of :meth:`flush`
+      using :func:`hasattr`
+      (rather than inspecting :const:`xml.parsers.expat.version_info`),
+      at runtime.
+
       .. versionadded:: 3.13
 
    .. method:: close()

Misc/NEWS.d/next/Documentation/2024-03-03-17-04-30.gh-issue-115398.FQICYA.rst

@@ -0,0 +1,2 @@
+Suggest use of :func:`hasattr` when checking for availability of Expat reparse
+deferral security API.