bpo-34160: Preserve user specified order of Element attributes (GH-10163)

diff --git a/Lib/xml/etree/ElementTree.py b/Lib/xml/etree/ElementTree.py
index 85586d0..d4df83f 100644
--- a/Lib/xml/etree/ElementTree.py
+++ b/Lib/xml/etree/ElementTree.py
@@ -923,7 +923,7 @@
                             k,
                             _escape_attrib(v)
                             ))
-                for k, v in sorted(items):  # lexical order
+                for k, v in items:
                     if isinstance(k, QName):
                         k = k.text
                     if isinstance(v, QName):