code: def register_endpoints(self):
          
          url_map = []
          redirect_path = urlparse(self.config["client"]["client_metadata"]["redirect_uris"][0]).path
          if not redirect_path:
              raise SATOSAError("Missing path in redirect uri")
  
          url_map.append(("^%s$" % redirect_path.lstrip("/"), self.response_endpoint))
          return url_map
docs: Creates a list of all the endpoints this backend module needs to listen to. In this case
          it's the authentication response from the underlying OP that is redirected from the OP to
          the proxy.
          :rtype: Sequence[(str, Callable[[satosa.context.Context], satosa.response.Response]]
          :return: A list that can be used to map the request to SATOSA to this endpoint.