How to work with JSON in Python?

JSON (JavaScript Object Notation) is a text-based format for data exchange. Python provides a built-in json module for working with it.

Main functions:

• json.dumps() — Python object → JSON string
• json.loads() — JSON string → Python object
• json.dump() — Python object → JSON file
• json.load() — JSON file → Python object

Serialization (Python → JSON):

import json

data = {
    "name": "Anna",
    "age": 25,
    "hobbies": ["reading", "swimming"],
    "active": True
}

# To a string
json_string = json.dumps(data, ensure_ascii=False, indent=2)
print(json_string)

# To a file
with open("data.json", "w", encoding="utf-8") as f:
    json.dump(data, f, ensure_ascii=False, indent=2)

Deserialization (JSON → Python):

# From a string
json_string = '{"name": "Anna", "age": 25}'
data = json.loads(json_string)
print(data["name"])  # Anna

# From a file
with open("data.json", "r", encoding="utf-8") as f:
    data = json.load(f)

Type mapping: