'Return instance uuids given an address.'

def get_fixed_ip_by_address(self, context, address):

    uuid_maps = self._get_instance_uuids_by_ip(context, address)
    if (len(uuid_maps) == 1):
        return uuid_maps[0]
    elif (not uuid_maps):
        raise exception.FixedIpNotFoundForAddress(address=address)
    else:
        raise exception.FixedIpAssociatedWithMultipleInstances(address=address)
