210 – Convert data to a JSON string

The function dumps from the module json can be used to convert data into a JSON string:

import json

data = {"key1": True, "key2": [73, 42, 10]}

dumped = json.dumps(data)
print(type(dumped), dumped)
# <class 'str'> {"key1": true, "key2": [73, 42, 10]}

The value dumped that is printed looks almost the same as the variable data, but you can see that the Boolean value True was converted to true, since True is not a valid JSON value.

This is useful if you need to pass JSON data to other functions or processes but if your goal is to write the JSON data to a file, use the function dump instead:

import json

data = {"key1": True, "key2": [73, 42, 10]}

with open("myfile.json", "w") as f:
    json.dump(data, f)