How do you add a value to a json object in python?

Question

First, accidents is a dictionary, and you can't write to a dictionary; you just set values in it.

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Functions Used:
How do I add values to a JSON in Python?
How do I add data to an existing JSON object?
How do you modify a JSON object in Python?
How do you add a string to a JSON object in Python?

So, what you want is:

for accident in accidents:
    accident['Turn'] = 'right'

The thing you want to write out is the new JSON—after you've finished modifying the data, you can dump it back to a file.

Ideally you do this by writing to a new file, then moving it over the original:

with open('sanfrancisco_crashes_cp.json') as json_file:
    json_data = json.load(json_file)
accidents = json_data['accidents']
for accident in accidents:
    accident['Turn'] = 'right'
with tempfile.NamedTemporaryFile(dir='.', delete=False) as temp_file:
    json.dump(temp_file, json_data)
os.replace(temp_file.name, 'sanfrancisco_crashes_cp.json')

But you can do it in-place if you really want to:

# notice r+, not rw, and notice that we have to keep the file open
# by moving everything into the with statement
with open('sanfrancisco_crashes_cp.json', 'r+') as json_file:
    json_data = json.load(json_file)
    accidents = json_data['accidents']
    for accident in accidents:
        accident['Turn'] = 'right'
    # And we also have to move back to the start of the file to overwrite
    json_file.seek(0, 0)
    json.dump(json_file, json_data)
    json_file.truncate()

If you're wondering why you got the specific error you did:

In Python—unlike many other languages—assignments aren't expressions, they're statements, which have to go on a line all by themselves.

But keyword arguments inside a function call have a very similar syntax. For example, see that tempfile.NamedTemporaryFile(dir='.', delete=False) in my example code above.

So, Python is trying to interpret your accident['Turn'] = 'right' as if it were a keyword argument, with the keyword accident['Turn']. But keywords can only be actual words (well, identifiers), not arbitrary expressions. So its attempt to interpret your code fails, and you get an error saying keyword can't be an expression.

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The full form of JSON is JavaScript Object Notation. It means that a script (executable) file which is made of text in a programming language, is used to store and transfer the data. Python supports JSON through a built-in package called JSON. To use this feature, we import the JSON package in Python script. The text in JSON is done through quoted-string which contains the value in key-value mapping within { }.

Functions Used:

json.loads(): json.loads() function is present in python built-in ‘json’ module. This function is used to parse the JSON string.

Syntax: json.loads(json_string)
Parameter: It takes JSON string as the parameter.
Return type: It returns the python dictionary object.

json.dumps(): json.dumps() function is present in python built-in ‘json’ module. This function is used to convert Python object into JSON string.

Syntax: json.dumps(object)
Parameter: It takes Python Object as the parameter.
Return type: It returns the JSON string.

update(): This method updates the dictionary with elements from another dictionary object or from an iterable key/value pair.

Syntax: dict.update([other])
Parameters: Takes another dictionary or an iterable key/value pair.
Return type: Returns None.

Example 1: Updating a JSON string.

Python3

import json

x = '{ "organization":"GeeksForGeeks",

"city":"Noida",

"country":"India"}'

y = {"pin":110096}

z = json.loads(x)

z.update(y)

print(json.dumps(z))

Output:

{“pin”: 110096, “organization”: “GeeksForGeeks”, “country”: “India”, “city”: “Noida”}

Example 2: Updating a JSON file. Suppose the JSON file looks like this.

How do you add a value to a json object in python?

We want to add another JSON data after emp_details. Below is the implementation.

Python3

import json

def write_json(new_data, filename='data.json'):

with open(filename,'r+') as file:

file_data = json.load(file)

file_data["emp_details"].append(new_data)

file.seek(0)

json.dump(file_data, file, indent = 4)

y = {"emp_name":"Nikhil",

"email": "",

"job_profile": "Full Time"

}

write_json(y)

Output:

How do I add values to a JSON in Python?

Method 1: Using json..

Import the json library with import json. ... .

Read the JSON file in a data structure using data = json. ... .

Update the Python data structure with the new entry (e.g., a new dictionary to append to the list). ... .

Write the updated JSON data back to the JSON file using json..

How do I add data to an existing JSON object?

Use push() method to add JSON object to existing JSON array in JavaScript. Just do it with proper array of objects .

How do you modify a JSON object in Python?

How to update a JSON file in Python.

a_file = open("sample_file.json", "r").

json_object = json. load(a_file).

a_file. close().

print(json_object).

json_object["d"] = 100..

a_file = open("sample_file.json", "w").

json. dump(json_object, a_file).

a_file. close().

How do you add a string to a JSON object in Python?

Use the json. loads() function. The json. loads() function accepts as input a valid string and converts it to a Python dictionary. This process is called deserialization – the act of converting a string to an object.

programming python

How do you add a value to a json object in python?

Functions Used:

Python3

Python3

How do I add values to a JSON in Python?

How do I add data to an existing JSON object?

How do you modify a JSON object in Python?

How do you add a string to a JSON object in Python?

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