How to use the flexget.event.event function in FlexGet

@event('plugin.register')
def register_plugin():
    plugin.register(PluginPyLoad, 'pyload', api_ver=2)

@event('plugin.register')
def register_plugin():
    plugin.register(NotifyTask, 'notify_task', api_ver=2)

@event('plugin.register')
def register_plugin():
    plugin.register(SearchBTN, 'btn', interfaces=['search'], api_ver=2)

@event('plugin.register')
def register_plugin():
    plugin.register(NzbSize, 'nzb_size', api_ver=2, builtin=True)

@event('manager.db_cleanup')
def db_cleanup(manager, session):
    session.query(Category).delete(synchronize_session=False)
    session.query(TermType).delete(synchronize_session=False)
    session.query(Term).delete(synchronize_session=False)

@event('plugin.register')
def register_plugin():
    plugin.register(
        UrlRewriteSerienjunkies, 'serienjunkies', interfaces=['urlrewriter', 'task'], api_ver=2
    )

@event('options.register', priority=0)
def register_parser_arguments():
    exec_parser = options.get_parser('execute')
    inject_parser = options.register_command(
        'inject',
        do_cli,
        add_help=False,
        parents=[exec_parser],
        help='inject an entry from command line into tasks',
        usage='%(prog)s title/url [url] [--accept] [--force] '
        '[--fields NAME=VALUE [NAME=VALUE...]] []',
        epilog=(
            'If only a URL and no title is given, Flexget will attempt to '
            'find a title in the URL\'s response headers.'
        ),
    )
    inject_group = inject_parser.add_argument_group('inject arguments')

@event('manager.db_cleanup')
def db_cleanup(manager, session):
    log.debug('TODO: Disabled because of ticket #1321')
    return

    # Remove seen fields over a year old
    result = session.query(SeenField).filter(SeenField.added < datetime.now() - timedelta(days=365)).delete()
    if result:
        log.verbose('Removed %d seen fields older than 1 year.' % result)

@event('plugin.register')
def register_plugin():
    plugin.register(UoccinEmit, 'uoccin_emit', api_ver=2)

@event('plugin.register')
def register_plugin():
    plugin.register(UrlRewriteGoogleCse, 'google_cse', interfaces=['urlrewriter'], api_ver=2)
    plugin.register(UrlRewriteGoogle, 'google', interfaces=['urlrewriter'], api_ver=2)