Get parseString method from DOMImplementation API

ERP5Diff.py

@@ -20,7 +20,9 @@
 #
 ##############################################################################
 try:
-  from Ft.Xml import Parse as parse, parseString
+  from Ft.Xml import Parse as parse
+  from Ft.Xml.Domlette import EntityReaderBase
+  parseString = EntityReaderBase().parseString
 except:
   from xml.dom.minidom import parse, parseString