Merge branch 'xml-etree-validate' of github.com:serhiy-storchaka/cpython into xml-etree-validate

Author: serhiy-storchaka

Lib/xml/etree/ElementTree.py

@@ -938,8 +938,6 @@ def _serialize_xml(write, elem, qnames, namespaces, *,
     if elem.tail:
         write(_escape_cdata(elem.tail, validate))
 
-_CDATA_CONTENT_ELEMENTS = {"script", "style", "xmp", "iframe", "noembed", "noframes"}
-
 _CDATA_CONTENT_ELEMENTS = {"script", "style", "xmp", "iframe", "noembed",
                            "noframes", "plaintext"}