How to use the offlineimap.imaputil function in offlineimap

if self.delim == None:
                listres = imapobj.list(self.reference, '""')[1]
                if listres == [None] or listres == None:
                    # Some buggy IMAP servers do not respond well to LIST "" ""
                    # Work around them.
                    listres = imapobj.list(self.reference, '"*"')[1]
                if listres == [None] or listres == None:
                    # No Folders were returned. This occurs, e.g. if the
                    # 'reference' prefix does not exist on the mail
                    # server. Raise exception.
                    err = "Server '%s' returned no folders in '%s'"% \
                        (self.repos.getname(), self.reference)
                    self.ui.warn(err)
                    raise Exception(err)
                self.delim, self.root = \
                     imaputil.imapsplit(listres[0])[1:]
                self.delim = imaputil.dequote(self.delim)
                self.root = imaputil.dequote(self.root)

            with self.connectionlock:
                self.assignedconnections.append(imapobj)
                self.lastowner[imapobj] = curThread.ident
            return imapobj
        except Exception as e:
            """If we are here then we did not succeed in getting a
            connection - we should clean up and then re-raise the
            error..."""

            self.semaphore.release()

            severity = OfflineImapError.ERROR.REPO
            if type(e) == gaierror:

(probably severity MESSAGE) if e.g. no message with
                  this UID could be found.
        """
        data = self._fetch_from_imap(str(uid), self.retrycount)

        # data looks now e.g.
        #[('320 (X-GM-LABELS (...) UID 17061 BODY[] {2565}','msgbody....')]
        # we only asked for one message, and that msg is in data[0].
        # msbody is in [0][1].
        body = data[0][1].replace("\r\n", "\n")

        # Embed the labels into the message headers
        if self.synclabels:
            m = re.search('X-GM-LABELS\s*[(](.*)[)]', data[0][0])
            if m:
                labels = set([imaputil.dequote(lb) for lb in imaputil.imapsplit(m.group(1))])
            else:
                labels = set()
            labels = labels - self.ignorelabels
            labels_str = imaputil.format_labels_string(self.labelsheader, sorted(labels))

            # First remove old label headers that may be in the message content retrieved
            # from gmail Then add a labels header with current gmail labels.
            body = self.deletemessageheaders(body, self.labelsheader)
            body = self.addmessageheader(body, '\n', self.labelsheader, labels_str)

        if len(body)>200:
            dbg_output = "%s...%s"% (str(body)[:150], str(body)[-50:])
        else:
            dbg_output = body

        self.ui.debug('imap', "Returned object from fetching %d: '%s'"%

def _messagelabels_aux(self, arg, uidlist, labels):
        """Common code to savemessagelabels and addmessagelabels"""
        labels = labels - self.ignorelabels
        uidlist = [uid for uid in uidlist if uid > 0]
        if len(uidlist) > 0:
            imapobj = self.imapserver.acquireconnection()
            try:
                labels_str = '(' + ' '.join([imaputil.quote(lb) for lb in labels]) + ')'
                # Coalesce uid's into ranges
                uid_str = imaputil.uid_sequence(uidlist)
                result = self._store_to_imap(imapobj, uid_str, arg, labels_str)

            except imapobj.readonly:
                self.ui.labelstoreadonly(self, uidlist, labels)
                return None

            finally:
                self.imapserver.releaseconnection(imapobj)

            if result:
                retlabels = imaputil.flags2hash(imaputil.imapsplit(result)[1])['X-GM-LABELS']
                retlabels = set([imaputil.dequote(lb) for lb in imaputil.imapsplit(retlabels)])
                return retlabels
        return None

def savemessagelabels(self, uid, labels, ignorelabels=set()):
        """Change a message's labels to `labels`.

        Note that this function does not check against dryrun settings,
        so you need to ensure that it is never called in a dryrun mode."""

        filename = self.messagelist[uid]['filename']
        filepath = os.path.join(self.getfullname(), filename)

        file = open(filepath, 'rt')
        content = file.read()
        file.close()

        oldlabels = set()
        for hstr in self.getmessageheaderlist(content, self.labelsheader):
            oldlabels.update(imaputil.labels_from_header(self.labelsheader, hstr))

        labels = labels - ignorelabels
        ignoredlabels = oldlabels & ignorelabels
        oldlabels = oldlabels - ignorelabels

        # Nothing to change
        if labels == oldlabels:
            return

        # Change labels into content
        labels_str = imaputil.format_labels_string(self.labelsheader,
          sorted(labels | ignoredlabels))

        # First remove old labels header, and then add the new one
        content = self.deletemessageheaders(content, self.labelsheader)
        content = self.addmessageheader(content, '\n', self.labelsheader, labels_str)

def makefolder_single(self, foldername):
        self.ui.makefolder(self, foldername)
        if self.account.dryrun:
            return
        imapobj = self.imapserver.acquireconnection()
        try:
            if self.account.utf_8_support:
                foldername = imaputil.utf8_IMAP(foldername)

            result = imapobj.create(foldername)
            if result[0] != 'OK':
                raise OfflineImapError("Folder '%s'[%s] could not be created. "
                    "Server responded: %s"% (foldername, self, str(result)),
                    OfflineImapError.ERROR.FOLDER)
        finally:
            self.imapserver.releaseconnection(imapobj)