Convert single quotes to double quotes for Dictionary key/value pair

Question

I have a dictionory with key value pair in single inverted commas as follows:

filename = 'sub-310621_task-EMOTION_acq-LR_bold.nii.gz'
intended_for ={"IntendedFor", filename}

AS i am want to write this dictionary to a json file i have to have filename in between two inverted commas eg: "sub-310621_task-EMOTION_acq-LR_bold.nii.gz"

SO the output should look like:

intended_for ={"IntendedFor", "sub-310621_task-EMOTION_acq-LR_bold.nii.gz"}

This output will be written in to test.json file which should look like:

{
    "IntendedFor": "sub-310621_task-EMOTION_acq-LR_bold.nii.gz"
}

How can i do this in python ?

Answer 1

Rather than trying to build the JSON string yourself you should use the json module to do the encoding.

The json.dumps() method takes an object such as a dictionary with key value pairs and converts it into a JSON compliant string which can then be written to a file.

Instead of a dictionary, you created a set by using a comma , instead of a colon :

intended_for = {"IntendedFor", filename}

The correct code for your input would be

filename = 'sub-310621_task-EMOTION_acq-LR_bold.nii.gz'
intended_for ={"IntendedFor": filename}

Then you can encode

import json
json_string = json.dumps(intended_for)

Answer 2

The apostrophes or quotation marks on the ends of a string literal are not included in the string - 'asdf' and "asdf" represent identical strings. Neither the key nor the value in your dict actually include the character ' or ", so you don't need to perform a conversion.

When you dump the dict to JSON, your JSON dumper will automatically surround strings with " characters, among other necessary escaping. For example, if you're using the json module, you can just do

json_string = json.dumps(intended_for)

to produce a correctly-formatted JSON string. (If this does not work, you have some other bug you're not showing us.)