How to parse a JSON in Python?

Question

I'm a beginner in Python, I'm doing an API request and receiving the following JSON:

{
    'data': {
        'timelines': [{
            'timestep': 'current',
            'startTime': '2021-05-29T14:46:00Z',
            'endTime': '2021-05-29T14:46:00Z',
            'intervals': [{
                'startTime': '2021-05-29T14:46:00Z',
                'values': {
                    'temperature': 21.92
                }
            }]
        }]
    }
}

I want to print the temperature and I read that I have to parse the JSON in order to use the date inside of it so I did this:

response = requests.request("GET", url, headers=headers, params=querystring)    
jsonunparsed = response.json()
parsed = json.loads(jsonunparsed)

I suppose to have a dictionary now but when I run this

print(parsed)

I have only one Key which is 'data'

Finally I decide to comment all the above and running the below code I'm able to print the temperature

response_json = response.json()
print(response_json['data']['timelines'][0]['intervals'][0]['values']['temperature'])

So my questions are, isn't mandatory to parse the json? Why is working my second option? when shall I parse the json using loads() and when shall I operate directly with it? What are the pros and cons of each option? How could I retrieve the temperature with the parsed json?

Thanks

Answer 1

response.json() is already a parsed JSON - requests does it for you, so there is no need to use json.loads()

You use json.loads() when dealing with a string, like:

unparsedJSON = "{'key': 'value'}"

parsedJSON = json.loads(unparsedJSON)

This would convert the string ( unparsedJSON ) into a dictionary.

If you were to use response.text instead of response.json() , then you could use json.loads() , but since requests can already do it for you, there's no reason to do this. If you were to do it however, it would look like this:

unparsedJSON = response.text

parsedJSON = json.loads(unparsedJSON)

Answer 2

response.json() already converts(or parses) the response object into JSON's equivalent Python object(Dictionary) so you don't need json.loads(jsonunparsed) call, provided it is a valid JSON. Else it will throw exception.

    jsonunparsed = response.json()
    parsed = json.loads(jsonunparsed)

So you can write it this way too

    jsonparsed = response.json()
    print(jsonparsed['data']['timelines'][0]['intervals'][0]['values']['temperature'])