When talking about interfaces, use the interface names, not the names

of the implementation classes.  (Remove the "Impl" from two names.)

Doc/lib/xmlsax.tex

@@ -59,7 +59,7 @@ not instantiated by the application itself.  Since Python does not have
 an explicit notion of interface, they are formally introduced as
 classes, but applications may use implementations which do not inherit
 from the provided classes.  The \class{InputSource}, \class{Locator},
-\class{AttributesImpl}, \class{AttributesNSImpl}, and
+\class{Attributes}, \class{AttributesNS}, and
 \class{XMLReader} interfaces are defined in the module
 \refmodule{xml.sax.xmlreader}.  The handler interfaces are defined in
 \refmodule{xml.sax.handler}.  For convenience, \class{InputSource}