#Python JSON

JSON is a syntax for storing and exchanging data. It is text, written with JavaScript Object Notation.

#JSON in Python

Python has a built-in package called json, which can be used to work with JSON data.

#Example

Import the json module:

pythonimport json

#Parse JSON - Convert from JSON to Python

If you have a JSON string, you can parse it by using the json.loads() method. The result will be a Python dictionary.

#Example

pythonimport json

# some JSON:
x =  '{ "name":"John", "age":30, "city":"New York"}'

# parse x:
y = json.loads(x)

# the result is a Python dictionary:
print(y["age"])

#Convert from Python to JSON

If you have a Python object, you can convert it into a JSON string by using the json.dumps() method.

#Example

pythonimport json

# a Python object (dict):
x = {
  "name": "John",
  "age": 30,
  "city": "New York"
}

# convert into JSON:
y = json.dumps(x)

# the result is a JSON string:
print(y)

You can convert Python objects of the following types into JSON strings:

dict
list
tuple
string
int
float
True
False
None

#Example

pythonimport json

print(json.dumps({"name": "John", "age": 30}))
print(json.dumps(["apple", "bananas"]))
print(json.dumps(("apple", "bananas")))
print(json.dumps("hello"))
print(json.dumps(42))
print(json.dumps(31.76))
print(json.dumps(True))
print(json.dumps(False))
print(json.dumps(None))

#Conversion Table

When you convert from Python to JSON, Python objects are converted into their JSON (JavaScript) equivalent:

Python	JSON
`dict`	Object
`list`	Array
`tuple`	Array
`str`	String
`int`	Number
`float`	Number
`True`	true
`False`	false
`None`	null

#Complex Example

Convert a Python object containing all legal data types:

pythonimport json

x = {
  "name": "John",
  "age": 30,
  "married": True,
  "divorced": False,
  "children": ("Ann","Billy"),
  "pets": None,
  "cars": [
    {"model": "BMW 230", "mpg": 27.5},
    {"model": "Ford Edge", "mpg": 24.1}
  ]
}

print(json.dumps(x))

#Format the Result

The example above prints a JSON string, but it is not very easy to read without indentations and line breaks. The json.dumps() method has parameters to make the result more readable.

#Indentation

Use the indent parameter to define the number of indents:

pythonjson.dumps(x, indent=4)

#Separators

You can also define the separators. The default value is (", ", ": "), which uses a comma and space to separate objects, and a colon and space to separate keys from values.

pythonjson.dumps(x, indent=4, separators=(". ", " = "))

#Order the Result

The json.dumps() method has parameters to order the keys in the result. Use the sort_keys parameter to specify if the result should be sorted alphabetically:

pythonjson.dumps(x, indent=4, sort_keys=True)