def _mergeBeaconInformation(self, newBeaconInformation):
        """
        Merges beacon information in the adapter state (if it exists) into
        the provided beacon information. Specifically, this merges used and
        seen beacons.

        If the adapter state has no beacon information, does nothing.

        @param beaconInformation: The beacon information object that beacon
            information will be merged into (if necessary).
        @type beaconInformation: L{twisted.positioning.base.BeaconInformation}
        """
        old = self._state.get('_partialBeaconInformation')
        if old is None:
            return

        for attr in ["seenBeacons", "usedBeacons"]:
            getattr(newBeaconInformation, attr).update(getattr(old, attr))

        Merges beacon information in the adapter state (if it exists) into
        the provided beacon information. Specifically, this merges used and
        seen beacons.

        If the adapter state has no beacon information, does nothing.

        @param beaconInformation: The beacon information object that beacon
            information will be merged into (if necessary).
        @type beaconInformation: L{twisted.positioning.base.BeaconInformation}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/positioning/nmea.py