How to use the ceilometer.NotImplementedError function in ceilometer

def _handle_metadata(self, op, field_name, value):
        if op == self.operators["in"]:
            raise ceilometer.NotImplementedError('Metadata query with in '
                                                 'operator is not implemented')
        field_name = field_name[len('resource_metadata.'):]
        meta_table = META_TYPE_MAP[type(value)]
        meta_alias = aliased(meta_table)
        on_clause = and_(self.table.internal_id == meta_alias.id,
                         meta_alias.meta_key == field_name)
        # outer join is needed to support metaquery
        # with or operator on non existent metadata field
        # see: test_query_non_existing_metadata_with_result
        # test case.
        self.query = self.query.outerjoin(meta_alias, on_clause)
        return op(meta_alias.value, value)

def clear_expired_event_data(ttl):
        """Clear expired data from the backend storage system.

        Clearing occurs according to the time-to-live.

        :param ttl: Number of seconds to keep records for.
        """
        raise ceilometer.NotImplementedError('Clearing events not implemented')

def get_events(event_filter, limit=None):
        """Return an iterable of model.Event objects."""
        raise ceilometer.NotImplementedError('Events not implemented.')

def get_samples(sample_filter, limit=None):
        """Return an iterable of model.Sample instances.

        :param sample_filter: Filter.
        :param limit: Maximum number of results to return.
        """
        raise ceilometer.NotImplementedError('Samples not implemented')

def get_event_types():
        """Return all event types as an iterable of strings."""
        raise ceilometer.NotImplementedError('Events not implemented.')

def query_samples(filter_expr=None, orderby=None, limit=None):
        """Return an iterable of model.Sample objects.

        :param filter_expr: Filter expression for query.
        :param orderby: List of field name and direction pairs for order by.
        :param limit: Maximum number of results to return.
        """

        raise ceilometer.NotImplementedError('Complex query for samples '
                                             'is not implemented.')

is_regex = True
        column = 'f:' + value
        r = {}
        for row in rows:
            data = rows[row]
            r_data = {}
            for key in data:
                if ((op == '=' and key.startswith(column)) or
                        (op == '>=' and key >= column) or
                        (op == '<=' and key <= column) or
                        (op == '>' and key > column) or
                        (op == '<' and key < column) or
                        (is_regex and re.search(value, key))):
                    r_data[key] = data[key]
                else:
                    raise ceilometer.NotImplementedError(
                        "In-memory QualifierFilter "
                        "doesn't support the %s "
                        "operation yet" % op)
            if r_data:
                r[row] = r_data
        return r

def update_alarm(alarm):
        """Update alarm."""
        raise ceilometer.NotImplementedError('Alarms not implemented')

def query_alarm_history(filter_expr=None, orderby=None, limit=None):
        """Return an iterable of model.AlarmChange objects.

        :param filter_expr: Filter expression for query.
        :param orderby: List of field name and direction pairs for order by.
        :param limit: Maximum number of results to return.
        """

        raise ceilometer.NotImplementedError('Complex query for alarms '
                                             'history is not implemented.')