def validCtxtNormalizeAttributeValue(self, ctxt, elem, name, value):
        """Does the validation related extra step of the normalization
          of attribute values:  If the declared value is not CDATA,
          then the XML processor must further process the normalized
          attribute value by discarding any leading and trailing
          space (#x20) characters, and by replacing sequences of
          space (#x20) characters by single space (#x20) character.
          Also  check VC: Standalone Document Declaration in P32, and
           update ctxt->valid accordingly """
        if ctxt is None: ctxt__o = None
        else: ctxt__o = ctxt._o
        if elem is None: elem__o = None
        else: elem__o = elem._o
        ret = libxml2mod.xmlValidCtxtNormalizeAttributeValue(ctxt__o, self._o, elem__o, name, value)
        return ret