How to use the voila.static_file_handler.WhiteListFileHandler function in voila

def get_absolute_path(self, root, path):
        # StaticFileHandler.get always calls this method first, so we use this as the
        # place to check the path. Note that now the path seperator is os dependent (\\ on windows)
        whitelisted = any(re.fullmatch(pattern, path) for pattern in self.whitelist)
        blacklisted = any(re.fullmatch(pattern, path) for pattern in self.blacklist)
        if not whitelisted:
            raise tornado.web.HTTPError(403, 'File not whitelisted')
        if blacklisted:
            raise tornado.web.HTTPError(403, 'File blacklisted')
        return super(WhiteListFileHandler, self).get_absolute_path(root, path)

# Serving notebook extensions
        if self.voila_configuration.enable_nbextensions:
            handlers.append(
                (
                    url_path_join(self.server_url, r'/voila/nbextensions/(.*)'),
                    FileFindHandler,
                    {
                        'path': self.nbextensions_path,
                        'no_cache_paths': ['/'],  # don't cache anything in nbextensions
                    },
                )
            )
        handlers.append(
            (
                url_path_join(self.server_url, r'/voila/files/(.*)'),
                WhiteListFileHandler,
                {
                    'whitelist': self.voila_configuration.file_whitelist,
                    'blacklist': self.voila_configuration.file_blacklist,
                    'path': self.root_dir,
                },
            )
        )

        tree_handler_conf = {
            'voila_configuration': self.voila_configuration
        }
        if self.notebook_path:
            handlers.append((
                url_path_join(self.server_url, r'/(.*)'),
                VoilaHandler,
                {

tree_handler_conf = {
        'voila_configuration': voila_configuration
    }
    web_app.add_handlers(host_pattern, [
        (url_path_join(base_url, '/voila/render/(.*)'), VoilaHandler, {
            'config': server_app.config,
            'nbconvert_template_paths': nbconvert_template_paths,
            'voila_configuration': voila_configuration
        }),
        (url_path_join(base_url, '/voila'), VoilaTreeHandler, tree_handler_conf),
        (url_path_join(base_url, '/voila/tree' + path_regex), VoilaTreeHandler, tree_handler_conf),
        (url_path_join(base_url, '/voila/static/(.*)'), MultiStaticFileHandler, {'paths': static_paths}),
        (
            url_path_join(base_url, r'/voila/files/(.*)'),
            WhiteListFileHandler,
            {
                'whitelist': voila_configuration.file_whitelist,
                'blacklist': voila_configuration.file_blacklist,
                'path': os.path.expanduser(web_app.settings['server_root_dir']),
            },
        ),
    ])

    # Serving notebook extensions
    if voila_configuration.enable_nbextensions:
        # First look into 'nbextensions_path' configuration key (classic notebook)
        # and fall back to default path for nbextensions (jupyter server).
        if 'nbextensions_path' in web_app.settings:
            nbextensions_path = web_app.settings['nbextensions_path']
        else:
            nbextensions_path = jupyter_path('nbextensions')