code: def add_handlers(web_app, config):
      
      base_url = web_app.settings['base_url']
      url = ujoin(base_url, config.page_url)
      assets_dir = config.assets_dir
  
      package_file = os.path.join(assets_dir, 'package.json')
      with open(package_file) as fid:
          data = json.load(fid)
  
      config.version = config.version or data['version']
      config.name = config.name or data['name']
  
      handlers = [
          # TODO Redirect to /tree
          (url + r'/?', NAppHandler, {'config': config, 'page': 'tree'}),
          (url + r"/tree%s" % path_regex, NAppHandler, {'config': config, 'page': 'tree'}),
          (url + r"/edit%s" % path_regex, NAppHandler, {'config': config, 'page': 'edit'}),
          (url + r"/view%s" % path_regex, NAppHandler, {'config': config, 'page': 'view'}),
          (url + r"/static/(.*)", FileFindHandler, {'path': assets_dir}),
      ]
  
      web_app.add_handlers(".*$", handlers)
docs: Add the appropriate handlers to the web app.