title: Python JSON add Key-Value pair
body: <p>I'm trying to add key value pairs into the existing JSON file. I am able to concatenate to the parent label, How to add value to the child items?</p>
  
  <p><strong>JSON file:</strong></p>
  
  <pre><code>{
    "students": [
      {
        "name": "Hendrick"
      },
      {
        "name": "Mikey"
      }
    ]
  }
  </code></pre>
  
  <p><strong>Code:</strong></p>
  
  <pre><code>import json
  
  with open("input.json") as json_file:
      json_decoded = json.load(json_file)
  
  json_decoded['country'] = 'UK'
  
  with open("output.json", 'w') as json_file:
      for d in json_decoded[students]:
          json.dump(json_decoded, json_file)
  </code></pre>
  
  <p><strong>Expected Results:</strong></p>
  
  <pre><code>{
    "students": [
      {
        "name": "Hendrick",
        "country": "UK"
      },
      {
        "name": "Mikey",
        "country": "UK"
      }
    ]
  }
  </code></pre>