bpo-34160: Preserve order of attributes in minidom. (GH-10219)

diff --git a/Lib/xml/dom/minidom.py b/Lib/xml/dom/minidom.py
index e44e04a..469c517 100644
--- a/Lib/xml/dom/minidom.py
+++ b/Lib/xml/dom/minidom.py
@@ -854,9 +854,8 @@
         writer.write(indent+"<" + self.tagName)
 
         attrs = self._get_attributes()
-        a_names = sorted(attrs.keys())
 
-        for a_name in a_names:
+        for a_name in attrs.keys():
             writer.write(" %s=\"" % a_name)
             _write_data(writer, attrs[a_name].value)
             writer.write("\"")