code: def reverse_params(url_name, params=None, **kwargs):
      
      url = reverse(url_name, **kwargs)
      params = urlencode(params if params else {})
      if params:
          return u"%s?%s" % (url, params)
      else:
          return url
docs: compute the reverse url of ``url_name`` and add to it parameters from ``params``
          as querystring
  
          :param unicode url_name: a URL pattern name
          :param params: Some parameter to append to the reversed URL
          :type params: :obj:`dict` or :obj:`NoneType<types.NoneType>`
          :param **kwargs: additional parameters needed to compure the reverse URL
          :return: The computed reverse URL of ``url_name`` with possible querystring from ``params``
          :rtype: unicode