docs: def invoke(self, request):
          """Invoke the given :class:`.Request` instance using the associated :class:`.Dispatcher`.
  
          :param request: :class:`.Request` instance to invoke.
          :return: :class:`.Resource` subclass.
          """
          url = '{0}/{1}'.format(self.base_url, request.remote_path)
          r = self.httpclient.get(url, params=request.params, headers=self.get_headers())
          if 200 <= r.status_code < 300:
              return self.resource_factory.from_json(r.json())
          else:
              if r.status_code in ErrorMapping.mapping:
                  raise ErrorMapping.mapping[r.status_code](r)
              else:
                  raise ApiError(r)