Python can't parse JSON with extra trailing comma

Question

This code:

import json
s = \'{ \"key1\": \"value1\", \"key2\": \"value2\", }\'
json.loads(s)

produces this error in Python 2:

Answer 1

It could be that this data stream is JSON5, in which case there's a parser for that: https://pypi.org/project/json5/

This situation can be alleviated by a regex substitution that looks for ", }, and replaces it with " }, allowing for any amount of whitespace between the quotes, comma and close-curly.

>>> import re
>>> s = '{ "key1": "value1", "key2": "value2", }'
>>> re.sub(r"\"\s*,\s*\}", "\" }", s)
'{ "key1": "value1", "key2": "value2" }'

Giving:

>>> import json
>>> s2 = re.sub(r"\"\s*,\s*\}", "\" }", s)
>>> json.loads(s2)
{'key1': 'value1', 'key2': 'value2'}

EDIT: as commented, this is not a good practice unless you are confident your JSON data contains only simple words, and this change is not corrupting the data-stream further. As I commented on the OP, the best course of action is to repair the up-stream data source. But sometimes that's not possible.