Turn text into data.
And data back into text.

JSON is a common text format for structured data. json.loads() parses JSON text into Python data; json.dumps() creates JSON text from Python data.

01 Learn02 Try03 Predict

01 Learn

JSON text can be converted to Python dictionaries and lists.

JSON is a common text format for structured data. json.loads() parses JSON text into Python data; json.dumps() creates JSON text from Python data.

import json

student_json = '{"name": "Ana", "score": 95}'
student = json.loads(student_json)
print(student["name"])

result = json.dumps(student)
print(result)

student_json is text, while student is a Python dictionary after loads(). dumps() makes JSON text again.

Ana
{"name": "Ana", "score": 95}

Change one value, then explain how the resulting data changes.

↳

Keep this in mind: Follow each data operation in order before predicting the result.

Try it

import json

student_json = '{"name": "Ana", "score": 95}'
student = json.loads(student_json)

print(student["name"])
student["score"] += 5
print(json.dumps(student))
# Change the JSON text or read another key

Run the example, then change one value and observe the result.

02 Try

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03 Predict

What will this program print?

Read each data operation before choosing an answer.

import json

course = json.loads('{"title": "Python", "students": 12}')
print(course["title"])
print(course["students"] + 1)

Your learning mentor

Ask Sloby about JSON data

Describe what feels unclear and Sloby will guide your reasoning.

Hi! I'm Sloby. Let's turn JSON text into useful Python data.

04 Understanding Check

What will this program print, and what is the difference between json.loads() and json.dumps()?

import json

data = json.loads('{"name": "Ana", "scores": [8, 9]}')
data["scores"].append(10)

print(data["name"])
print(len(data["scores"]))
print(json.dumps(data))