JSON.parse error while writing json data into json file

Question

I am trying to get JSON data from a localhost URL row by row and insert it into a JSON file. When I try to open the file, I receive an error that says Multiple JSON root elements.

import urllib.parse
import urllib.request, json 
import json
abc={}

for i in range(6666,6669):
    print(i)
    full_url="http://localhost/get/info" + str(i)
    with urllib.request.urlopen(full_url) as url:
        data = json.loads(url.read().decode())
        print(data['id'])
    abc={i:[data]}
    with open('data.json', 'a') as outfile:
        json.dump(abc,outfile)

Answer 1

A valid json object must have only one root

See How to read a JSON file containing multiple root elements?

You must append all json objects to an array and then write it to the json file

Resulting json object must be like

[
{ object 1 },
{ object 2 }
]

notice that there's only one root object in the json, the array containing all of the other objects