class_docstr: 执行评测时使用的 backend，是所有 backend 的父类。Backend 及其子类的所有方法都必须是无状态的。
class_docstr_tok: ["\u6267\u884c\u8bc4\u6d4b\u65f6\u4f7f\u7528\u7684","backend\uff0c\u662f\u6240\u6709","backend","\u7684\u7236\u7c7b\u3002Backend","\u53ca\u5176\u5b50\u7c7b\u7684\u6240\u6709\u65b9\u6cd5\u90fd\u5fc5\u987b\u662f\u65e0\u72b6\u6001\u7684\u3002"]
docstr: 给定 ``obj`` 将各个 rank 上的 ``obj`` 汇总到每个 ``obj`` 上。返回一个 :class:`list` 对象，里面依次为各个 rank 对应的 ``obj`` 。
  
  :param obj:
  :param group:
  :return:
docstr_tok: ["\u7ed9\u5b9a","``","obj","``","\u5c06\u5404\u4e2a","rank","\u4e0a\u7684","``","obj","``","\u6c47\u603b\u5230\u6bcf\u4e2a","``","obj","``","\u4e0a\u3002\u8fd4\u56de\u4e00\u4e2a",":","class",":","`","list","`","\u5bf9\u8c61\uff0c\u91cc\u9762\u4f9d\u6b21\u4e3a\u5404\u4e2a","rank","\u5bf9\u5e94\u7684","``","obj","``","\u3002",":","param","obj",":",":","param","group",":",":","return",":"]
code: def all_gather_object(self, obj, group=None):
      """
      给定 ``obj`` 将各个 rank 上的 ``obj`` 汇总到每个 ``obj`` 上。返回一个 :class:`list` 对象，里面依次为各个 rank 对应的 ``obj`` 。
  
      :param obj:
      :param group:
      :return:
      """
      if self.__class__.__name__ == "AutoBackend":
          raise RuntimeError(
              "fastNLP cannot determine the backend automatically, please pass in the backend through "
              "initialization."
          )
  
      raise NotImplementedError(
          f"all_gather_object() function is not implemented for {self.__class__.__name__}."
      )
  
file_path: fastNLP/fastNLP/core/metrics/backend/backend.py
imports: from ..utils import AggregateMethodError
label_desc: Use image node_id 9 for calling the Backend obj's underlying member method code with example usage: obj.all_gather_object(obj, group) without return types