code: def add_link_headers(response, links):
      
      link_string = '<{}>; rel=self'.format(links['self'])
      for link in links.values():
          link_string += ', <{}>; rel=related'.format(link)
      response.headers['Link'] = link_string
      return response
docs: Return *response* with the proper link headers set, based on the contents
      of *links*.
  
      :param response: :class:`flask.Response` response object for links to be
                       added
      :param dict links: Dictionary of links to be added
      :rtype :class:`flask.Response` :