varjson={"workbookInformation":{"version":"9.1","source-platform":"win"},"datasources1":{...},"datasources2":{...}}我需要在workbookInformation下添加新的key对，例如varjson={"workbookInformation":{"version":"9.1","source-platform":"win","new_key":"new_value"},"datasources1":{...},"datasources2":{...}}json['new