How to use the pyfuse3.ROOT_INODE 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)

from pyfuse3 import ROOT_INODE

VERSION = '3.3.2'
RELEASE = '%s' % VERSION

# TODO: On next revision bump, remove upgrade code from backend/comprenc.py and
# backends/s3c.py (activated by UPGRADE_MODE variable).
CURRENT_FS_REV = 24

# Buffer size when writing objects
BUFSIZE = 64 * 1024

# Name and inode of the special s3ql control file
CTRL_NAME = '.__s3ql__ctrl__'
CTRL_INODE = ROOT_INODE+1

# Maps file system revisions to the last S3QL version that
# supported this revision.
REV_VER_MAP = {
    23: '2.26',
    22: '2.16',
    21: '2.13',
    20: '2.9',
    16: '1.15',
    15: '1.10',
    14: '1.8.1',
    13: '1.6',
    12: '1.3',
    11: '1.0.1',
    }

def __init__(self, argv_prefix=("bash", "-c"), separator=b"|"):
        super(pyfuse3.Operations, self).__init__()
        signal.signal(signal.SIGCHLD, signal.SIG_IGN)
        self.argv_prefix = list(argv_prefix)
        self.separator = separator
        self._inode_generator = count(start=10)
        self._file_generator = count(start=10)
        self._inode_map = {pyfuse3.ROOT_INODE: Node(None, None,
                                                    pyfuse3.ROOT_INODE,
                                                    is_root=True)}
        self._proc_map = {}

def __init__(self, argv_prefix=("bash", "-c"), separator=b"|"):
        super(pyfuse3.Operations, self).__init__()
        signal.signal(signal.SIGCHLD, signal.SIG_IGN)
        self.argv_prefix = list(argv_prefix)
        self.separator = separator
        self._inode_generator = count(start=10)
        self._file_generator = count(start=10)
        self._inode_map = {pyfuse3.ROOT_INODE: Node(None, None,
                                                    pyfuse3.ROOT_INODE,
                                                    is_root=True)}
        self._proc_map = {}

def __init__(self, block_cache, db, max_obj_size, inode_cache,
                 upload_event=None):
        super().__init__()

        self.inodes = inode_cache
        self.db = db
        self.upload_event = upload_event
        self.open_inodes = collections.defaultdict(lambda: 0)
        self.max_obj_size = max_obj_size
        self.cache = block_cache
        self.failsafe = False
        self.broken_blocks = collections.defaultdict(set)

        # Root inode is always open
        self.open_inodes[pyfuse3.ROOT_INODE] += 1