import fileinput from string import join import json import csv import json with open('/home/vagrant/moutput/part-r-00000','rb') as csv_file: csv_reader = csv.reader(csv_file,delimiter='\t') old_id = "" indicators = [] update = {"update" : {"_id":""}} doc = {"doc" : {"indicators":[],"numFields":0}} for row in csv_reader: id = row[0] if (id != old_id and old_id != "") : update["update"]["_id"] = old_id doc["doc"]["indicators"] = indicators doc["doc"]["numFields"] = len(indicators) print(json.dumps(update)) print(json.dumps(doc)) indicators = [row[1]] else: indicators.append(row[1]) old_id = id