split the NEWS entry into two, and simplify _guess_media_encoding

Author: tungol

Lib/xml/dom/xmlbuilder.py

@@ -247,10 +247,11 @@ def _create_opener(self):
 
     def _guess_media_encoding(self, source):
         info = source.byteStream.info()
-        if "Content-Type" in info:
-            for param in info.get_params([]):
-                if param[0] == 'charset':
-                    return param[1].lower()
+        # import email.message
+        # assert isinstance(info, email.message.Message)
+        for ctp_name, ctp_value in info.get_params(()):
+            if ctp_name == 'charset':
+                return ctp_value.lower()
 
 
 class DOMInputSource(object):

Misc/NEWS.d/next/Library/2024-12-27-16-28-57.gh-issue-128302.2GMvyl.rst

@@ -1,4 +1,3 @@
 Allow :meth:`!xml.dom.xmlbuilder.DOMParser.parse` to correctly handle
 :class:`!xml.dom.xmlbuilder.DOMInputSource` instances that only have a
-:attr:`!systemId` attribute set. Also, fix the broken
-:meth:`!xml.dom.xmlbuilder.DOMEntityResolver.resolveEntity` method.
+:attr:`!systemId` attribute set.

Misc/NEWS.d/next/Library/2024-12-29-13-49-46.gh-issue-128302.psRpPN.rst

@@ -0,0 +1,2 @@
+Fix :meth:`!xml.dom.xmlbuilder.DOMEntityResolver.resolveEntity`, which was
+broken by the Python 3.0 transition.