def smart_search(cls, query_string, search_options=None, extra_query = None):
        """ Perform a smart VRF search.

            Maps to the function
            :py:func:`nipap.backend.Nipap.smart_search_vrf` in the backend.
            Please see the documentation for the backend function for
            information regarding input arguments and return values.
        """

        if search_options is None:
            search_options = {}

        xmlrpc = XMLRPCConnection()
        try:
            smart_result = xmlrpc.connection.smart_search_vrf(
                {
                    'query_string': query_string,
                    'search_options': search_options,
                    'auth': AuthOptions().options,
                    'extra_query': extra_query
                })
        except xmlrpclib.Fault as xml_fault:
            raise _fault_to_exception(xml_fault)
        result = dict()
        result['interpretation'] = smart_result['interpretation']
        result['search_options'] = smart_result['search_options']
        result['error'] = smart_result['error']
        if 'error_message' in smart_result:
            result['error_message'] = smart_result['error_message']
        result['result'] = list()
        for v in smart_result['result']:
            result['result'].append(VRF.from_dict(v))

        return result
Perform a smart VRF search.

            Maps to the function
            :py:func:`nipap.backend.Nipap.smart_search_vrf` in the backend.
            Please see the documentation for the backend function for
            information regarding input arguments and return values.