xpathns.py contained a use after free. It runs during make test

and is shipped in share/examples.
ok aja

textproc/libxml/Makefile

@@ -8,7 +8,7 @@ PKGNAME-main=		libxml-${VERSION}
 PKGNAME-python=		py3-libxml-${VERSION}
 
 REVISION-main=		1
-REVISION-python=	2
+REVISION-python=	3
 
 SHARED_LIBS +=  xml2                 18.0     # 12.3
 

textproc/libxml/patches/patch-python_tests_xpathns_py

@@ -0,0 +1,20 @@
+https://gitlab.gnome.org/GNOME/libxml2/-/commit/97c0a9cff728f5091771509567185c26a26669b4
+Index: python/tests/xpathns.py
+--- python/tests/xpathns.py.orig
++++ python/tests/xpathns.py
+@@ -11,6 +11,7 @@ d = libxml2.parseDoc("<a:a xmlns:a='urn:whatevar'/>")
+ res=""
+ for n in d.xpathEval("//namespace::*"):
+     res = res + n.serialize()
++del n
+ d.freeDoc()
+ 
+ if res != expect:
+@@ -18,7 +19,6 @@ if res != expect:
+     print(res)
+ del res
+ del d
+-del n
+ # Memory debug specific
+ libxml2.cleanupParser()
+