def validateElement(self, ctxt, elem):
        """Try to validate the subtree under an element """
        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.xmlValidateElement(ctxt__o, self._o, elem__o)
        return ret