Issue #26182: Raise DeprecationWarning for improper use of async/await keywords
diff --git a/Lib/xml/dom/xmlbuilder.py b/Lib/xml/dom/xmlbuilder.py
index 444f0b2..e9a1536 100644
--- a/Lib/xml/dom/xmlbuilder.py
+++ b/Lib/xml/dom/xmlbuilder.py
@@ -353,14 +353,14 @@
 class DocumentLS:
     """Mixin to create documents that conform to the load/save spec."""
 
-    async = _AsyncDeprecatedProperty()
     async_ = False
+    locals()['async'] = _AsyncDeprecatedProperty()  # Avoid DeprecationWarning
 
     def _get_async(self):
         return False
 
-    def _set_async(self, async):
-        if async:
+    def _set_async(self, flag):
+        if flag:
             raise xml.dom.NotSupportedErr(
                 "asynchronous document loading is not supported")