Python json why is it throwing an error?

Question

Python

python file:

import json
with open('test.json', 'r') as f:
  data = json.load(f)

  for items in data:
    items["1"] += [1, 2]

with open('test.json', 'w') as f:
  json.dump(data, f, indent=3)

json file:

[
   {
      "1": []
   },
   {
      "2": []
   }
]

Mistake:

items["1"] += [1, 2]
KeyError: '1'

Answer 1

And what about json? there is a dictionary . It has one key - the number 2. You are trying to get the element with the key "1":{"2": []}items["1"]