def online_offline_drive(drive, onoffline):
    log.debug(f'online_offline_drive() called with [{drive}] , [{onoffline}]')
    if get_device_info_by_drive_number(drive) == None:
        log.debug(f'Drive: {drive} does not exist or is not mounted on this system!')
    else:
        if onoffline == 'offline':
            offlined_drives = []
            with open('offlined_drives', 'r') as offlined_drives_list:
                offlined_drives = [current_drives.rstrip() for current_drives in offlined_drives_list.readlines()]
                if drive in offlined_drives:
                    log.debug(f'Drive: {drive} Already in offline mode!')
                else:
                    offlined_drives.append(drive)
                    with open('offlined_drives', 'w') as offlined_drive_list:
                        offlined_drive_list.writelines("%s\n"  % drives for drives in offlined_drives)
                        log.debug(f'Drive: {drive} Put into OFFLINE mode! Plots will not be written to this drive!')
        elif onoffline == 'online':
            offlined_drives = []
            with open('offlined_drives', 'r') as offlined_drives_list:
                offlined_drives = [current_drives.rstrip() for current_drives in offlined_drives_list.readlines()]
                if drive in offlined_drives:
                    offlined_drives.remove(drive)
                    with open('offlined_drives', 'w') as offlined_drive_list:
                        offlined_drive_list.writelines("%s\n"  % drives for drives in offlined_drives)
                        log.debug(f'Drive: {drive} Put into ONLINE mode! Plots will now be written to this drive!')
                else:
                    log.debug(f'Drive: {drive} was not offline!')
        elif onoffline == 'check':
            with open('offlined_drives', 'r') as offlined_drives_list:
                offlined_drives = [current_drives.rstrip() for current_drives in offlined_drives_list.readlines()]
                if drive in offlined_drives:
                    return True
                else:
                    return False