def update_state(self, up_to_timestamp):
        """
        Call this function to ensure that the channel is up to date at the time of timestamp.
        I.e., all the streams that have been created before or at that timestamp are calculated exactly until
        up_to_timestamp.
        """
        for stream_id in self.streams:
            self.streams[stream_id].calculated_intervals = TimeIntervals([(MIN_DATE, up_to_timestamp)])
        self.up_to_timestamp = up_to_timestamp
Call this function to ensure that the channel is up to date at the time of timestamp.
        I.e., all the streams that have been created before or at that timestamp are calculated exactly until
        up_to_timestamp.