FreeOpcUa / python-opcua

        if count and len(evts) > count:

            evts.pop(0)

    def read_event_history(self, source_id, start, end, nb_values, evfilter):

        cont = None

        if source_id not in self._events:

            print("Error attempt to read event history for a node which does not historize events")

            return [], cont

        else:

            if start is None:

                start = ua.DateTimeMinValue

            if end is None:

                end = ua.DateTimeMinValue

            if start == ua.DateTimeMinValue:

                results = [ev for ev in reversed(self._events[source_id]) if start <= ev.Time]

            elif end == ua.DateTimeMinValue:

                results = [ev for ev in self._events[source_id] if start <= ev.Time]

            elif start > end:

                results = [ev for ev in reversed(self._events[source_id]) if end <= ev.Time <= start]

            else:

                results = [ev for ev in self._events[source_id] if start <= ev.Time <= end]

            if nb_values and len(results) > nb_values:

                cont = results[nb_values + 1].Time

                results = results[:nb_values]

            return results, cont

    def stop(self):

        pass

        if count and len(data) > count:

            data.pop(0)

    def read_node_history(self, node_id, start, end, nb_values):

        cont = None

        if node_id not in self._datachanges:

            print("Error attempt to read history for a node which is not historized")

            return [], cont

        else:

            if start is None:

                start = ua.DateTimeMinValue

            if end is None:

                end = ua.DateTimeMinValue

            if start == ua.DateTimeMinValue:

                results = [dv for dv in reversed(self._datachanges[node_id]) if start <= dv.ServerTimestamp]

            elif end == ua.DateTimeMinValue:

                results = [dv for dv in self._datachanges[node_id] if start <= dv.ServerTimestamp]

            elif start > end:

                results = [dv for dv in reversed(self._datachanges[node_id]) if end <= dv.ServerTimestamp <= start]

            else:

                results = [dv for dv in self._datachanges[node_id] if start <= dv.ServerTimestamp <= end]

            if nb_values and len(results) > nb_values:

                cont = results[nb_values + 1].ServerTimestamp

                results = results[:nb_values]

            return results, cont

    def new_historized_event(self, source_id, evtypes, period, count=0):

        if source_id in self._events: