How to use the py2app.util.fsencoding function in py2app

def iter_data_files(self):
        dist = self.distribution
        allres = chain(getattr(dist, 'data_files', ()) or (), self.resources)
        for (path, files) in (normalize_data_file(fn) for fn in allres):
            path = fsencoding(path)
            for fn in files:
                fn = fsencoding(fn)
                yield fn, os.path.join(path, os.path.basename(fn))

def iter_datamodels(self, resdir):
        for (path, files) in (normalize_data_file(fn) for fn in (self.datamodels or ())):
            path = fsencoding(path)
            for fn in files:
                fn = fsencoding(fn)
                basefn, ext = os.path.splitext(fn)
                if ext != '.xcdatamodel':
                    basefn = fn
                    fn += '.xcdatamodel'
                destfn = os.path.basename(basefn) + '.mom'
                yield fn, os.path.join(resdir, path, destfn)

def iter_datamodels(self, resdir):
        for (path, files) in (normalize_data_file(fn) for fn in (self.datamodels or ())):
            path = fsencoding(path)
            for fn in files:
                fn = fsencoding(fn)
                basefn, ext = os.path.splitext(fn)
                if ext != '.xcdatamodel':
                    basefn = fn
                    fn += '.xcdatamodel'
                destfn = os.path.basename(basefn) + '.mom'
                yield fn, os.path.join(resdir, path, destfn)

def iter_mappingmodels(self, resdir):
        for (path, files) in (normalize_data_file(fn) for fn in (self.mappingmodels or ())):
            path = fsencoding(path)
            for fn in files:
                fn = fsencoding(fn)
                basefn, ext = os.path.splitext(fn)
                if ext != '.xcmappingmodel':
                    basefn = fn
                    fn += '.xcmappingmodel'
                destfn = os.path.basename(basefn) + '.cdm'
                yield fn, os.path.join(resdir, path, destfn)

def create_pluginbundle(self, target, script, use_runtime_preference=True):
        base = target.get_dest_base()
        appdir = os.path.join(self.dist_dir, os.path.dirname(base))
        appname = self.get_appname()
        print("*** creating plugin bundle: %s ***" % (appname,))
        if self.runtime_preferences and use_runtime_preference:
            self.plist.setdefault(
                'PyRuntimeLocations', self.runtime_preferences)
        appdir, plist = create_pluginbundle(
            appdir,
            appname,
            plist=self.plist,
            extension=self.extension,
            arch=self.arch,
        )
        appdir = fsencoding(appdir)
        resdir = os.path.join(appdir, 'Contents', 'Resources')
        return appdir, resdir, plist