大家好，我正在使用MongoDB数据库，其中每个数据行如下:{"_id":ObjectId("5cf12696e81744d2dfc0000c"),"contributor":"user1","title":"Title1","userhasRate":["51","52",],"ratings":[4,3],}我需要将其更改为:{"_id":ObjectId("5cf12696e81744d2dfc0000c"),"contributor":"user1","title":"Title1",rate:[{userhasrate:"51",value:4},{userhasrate:"