I have JSON data like below. 

```
{  
   "market":[  
      {  
         "aciklama":"Migros",
         "kategori":"market",
         "odeme_tipi":"kredi_karti",
         "tarih":{  
            "seconds":1557673429,
            "nanoseconds":599000000
         },
         "tutar":"10",
         "user_email":"xyz@gmail.com",
         "user_uid":"6xx"
      },
      {  
         "aciklama":"Pidesi",
         "kategori":"market",
         "odeme_tipi":"nakit",
         "tarih":{  
            "seconds":1557173938,
            "nanoseconds":955000000
         },
         "tutar":"5",
         "user_email":"xyz@gmail.com",
         "user_uid":"6xx"
      }
   ],
   "diger":[  
      {  
         "aciklama":"Tatlı",
         "kategori":"diger",
         "odeme_tipi":"nakit",
         "tarih":{  
            "seconds":1557591963,
            "nanoseconds":180000000
         },
         "tutar":"20",
         "user_email":"xyz@gmail.com",
         "user_uid":"6xx"
      }
   ]
}

```

I want to get the sum of subnodes of `market`, `diger` via `tutar` property and want to extract this result with underscore.js:

```
market: 15 
diger: 20

```

I tried [reduce](https://underscorejs.org/#reduce) function of undersore.js but I could not. What is the best way to extract child nodes and process it?