docs: def list(self, options=None, **kwds):
          """
          Endpoint: /activities[/<options>]/list.json
  
          Returns a list of Activity objects.
          The options parameter can be used to narrow down the activities.
          Eg: options={"type": "photo-upload"}
          """
          option_string = self._build_option_string(options)
          activities = self._client.get("/activities%s/list.json" % option_string,
                                        **kwds)["result"]
          activities = self._result_to_list(activities)
          return [Activity(self._client, activity) for activity in activities]