How to use the pyfuse3.setxattr function in pyfuse3

def tst_bug382(self):
        dirname = self.newname()
        fullname = self.mnt_dir + "/" + dirname
        os.mkdir(fullname)
        assert stat.S_ISDIR(os.stat(fullname).st_mode)
        assert dirname in pyfuse3.listdir(self.mnt_dir)
        cmd = ('(%d, %r)' % (pyfuse3.ROOT_INODE, path2bytes(dirname))).encode()
        pyfuse3.setxattr('%s/%s' % (self.mnt_dir, CTRL_NAME), 'rmtree', cmd)
        # Invalidation is asynchronous...
        try:
            retry(5, lambda: not os.path.exists(fullname))
        except RetryTimeoutError:
            pass # assert_raises should fail
        assert_raises(FileNotFoundError, os.stat, fullname)
        assert dirname not in pyfuse3.listdir(self.mnt_dir)

def main(args=None):
    '''Control a mounted S3QL File System.'''

    if args is None:
        args = sys.argv[1:]

    options = parse_args(args)
    setup_logging(options)

    path = options.mountpoint

    ctrlfile = assert_fs_owner(path, mountpoint=True)

    if options.action == 'flushcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_flushcache!', b'dummy')

    elif options.action == 'dropcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_dropcache!', b'dummy')

    elif options.action == 'upload-meta':
        pyfuse3.setxattr(ctrlfile, 'upload-meta', b'dummy')

    elif options.action == 'log':
        level = getattr(logging, options.level.upper())
        cmd = ('(%r, %r)' % (level, ','.join(options.modules))).encode()
        pyfuse3.setxattr(ctrlfile, 'logging', cmd)

    elif options.action == 'cachesize':
        pyfuse3.setxattr(ctrlfile, 'cachesize', ('%d' % (options.cachesize * 1024,)).encode())

options = parse_args(args)
    setup_logging(options)

    path = options.mountpoint

    ctrlfile = assert_fs_owner(path, mountpoint=True)

    if options.action == 'flushcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_flushcache!', b'dummy')

    elif options.action == 'dropcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_dropcache!', b'dummy')

    elif options.action == 'upload-meta':
        pyfuse3.setxattr(ctrlfile, 'upload-meta', b'dummy')

    elif options.action == 'log':
        level = getattr(logging, options.level.upper())
        cmd = ('(%r, %r)' % (level, ','.join(options.modules))).encode()
        pyfuse3.setxattr(ctrlfile, 'logging', cmd)

    elif options.action == 'cachesize':
        pyfuse3.setxattr(ctrlfile, 'cachesize', ('%d' % (options.cachesize * 1024,)).encode())

if options.action == 'flushcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_flushcache!', b'dummy')

    elif options.action == 'dropcache':
        pyfuse3.setxattr(ctrlfile, 's3ql_dropcache!', b'dummy')

    elif options.action == 'upload-meta':
        pyfuse3.setxattr(ctrlfile, 'upload-meta', b'dummy')

    elif options.action == 'log':
        level = getattr(logging, options.level.upper())
        cmd = ('(%r, %r)' % (level, ','.join(options.modules))).encode()
        pyfuse3.setxattr(ctrlfile, 'logging', cmd)

    elif options.action == 'cachesize':
        pyfuse3.setxattr(ctrlfile, 'cachesize', ('%d' % (options.cachesize * 1024,)).encode())

def blocking_umount(mountpoint):
    '''Invoke fusermount and wait for daemon to terminate.'''

    with open('/dev/null', 'wb') as devnull:
        if subprocess.call(['fuser', '-m', mountpoint], stdout=devnull,
                           stderr=devnull) == 0:
            raise MountInUseError(mountpoint)

    ctrlfile = os.path.join(mountpoint, CTRL_NAME)

    log.debug('Flushing cache...')
    pyfuse3.setxattr(ctrlfile, 's3ql_flushcache!', b'dummy')

    # Get pid
    log.debug('Trying to get pid')
    pid = parse_literal(pyfuse3.getxattr(ctrlfile, 's3ql_pid?'), int)
    log.debug('PID is %d', pid)

    # Get command line to make race conditions less-likely
    cmdline = get_cmdline(pid)

    # Unmount
    log.debug('Unmounting...')

    if os.getuid() == 0 or platform.system() == 'Darwin':
        # MacOS X always uses umount rather than fusermount
        umount_cmd = ['umount', mountpoint]
    else:

def main(args=None):
    '''Make directory tree immutable'''

    if args is None:
        args = sys.argv[1:]

    options = parse_args(args)
    setup_logging(options)

    for name in options.path:
        if os.path.ismount(name):
            raise QuietError('%s is a mount point.' % name)
        ctrlfile = assert_fs_owner(name)
        fstat = os.stat(name)
        pyfuse3.setxattr(ctrlfile, 'lock', ('%d' % fstat.st_ino).encode())