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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _serve_plugins_listing(self, request):
 """Serves an object mapping plugin name to whether it is enabled. Args: request: The werkzeug.Request object. Returns: A werkzeug.Response object. """

    response = {}
    for plugin in self._plugins:
      start = time.time()
      response[plugin.plugin_name] = plugin.is_active()
      elapsed = time.time() - start
      logger.info(
          'Plugin listing: is_active() for %s took %0.3f seconds',
          plugin.plugin_name, elapsed)
    return http_util.Respond(request, response, 'application/json')