How to use the pyfuse3.Operations function in pyfuse3

# support extended attributes at all. A test with btrfs mounted with
# -o noacl shows that the actual errno returned by setxattr() is
# EOPNOTSUPP. Also, some Python versions do not know about
# errno.ENOTSUPP and errno(3) says that on Linux, EOPNOTSUPP and ENOTSUP
# have the same value (despite this violating POSIX).
#
# All in all, the situation seems complicated, so we try to use
# EOPNOTSUPP with a fallback on ENOTSUP just in case.

if not hasattr(errno, 'EOPNOTSUPP'):
    ACL_ERRNO = errno.ENOTSUP
else:
    ACL_ERRNO = errno.EOPNOTSUPP


class Operations(pyfuse3.Operations):
    """A full-featured file system for online data storage

    This class implements low-level FUSE operations and is meant to be passed to
    pyfuse3.init().

    The ``access`` method of this class always gives full access, independent of
    file permissions. If the FUSE library is initialized with ``allow_other`` or
    ``allow_root``, the ``default_permissions`` option should therefore always
    be passed as well.


    Attributes:
    -----------

    :cache:       Holds information about cached blocks
    :inode_cache: A cache for the attributes of the currently opened inodes.

p = self.parent.make_path(sep)
            if self.is_last:
                return p if p else b""
            if p:
                return p + sep + self.translated
            else:
                return self.translated
        return None

    def __repr__(self):
        return "" % (self.num, self.name, self.make_path())

    def add_child(self, child):
        self.children[child.name] = child

class BashFS(pyfuse3.Operations):
    enable_writeback_cache = False

    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 _make_child_node(self, node_p, name):
        new_num = next(self._inode_generator)

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 = {}