Python: encoding a file as you write it

Question

I'm using python 2.7 and I'm trying to write a file with some encoding (in my 'finalList' variable the encoding is: 0xe9)

This is how I'm trying to write my file using the 'json' and 'io' modules

import json
import io

with io.open('my.json', 'w', encoding='utf8') as outfile:
    json.dump(finalList, outfile)

Possible duplicate of [Backporting Python 3 open(encoding="utf-8") to Python 2](http://stackoverflow.com/questions/10971033/backporting-python-3-openencoding-utf-8-to-python-2) — Jean-François Fabre, Jan 16 '17 at 20:48
I just added it from the example here: http://stackoverflow.com/questions/10971033/backporting-python-3-openencoding-utf-8-to-python-2 ..but now I'm getting this error: name 'io' is not defined — NewToJS, Jan 16 '17 at 21:17
You need to `import io` to use `io.open()`, or `import codecs` and use `codecs.open()`. Both should work. Or better, use the answer jcomeau_ictx suggests. — Georg Schölly, Jan 16 '17 at 21:32
I'm not using io.open and changed my code in my question...but getting this error: json.dump(finalList, outfile) File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/__init__.py", line 190, in dump fp.write(chunk) TypeError: must be unicode, not str — NewToJS, Jan 16 '17 at 21:36

score 1 · Answer 1 · answered Jan 16 '17 at 21:29

1

json.dump accepts an encoding arg which defaults to 'utf-8':

$ pydoc json.dump
Help on function dump in json:

json.dump = dump(obj, fp, skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, cls=None, indent=None, separators=None, encoding='utf-8', default=None, sort_keys=False, **kw)

answered Jan 16 '17 at 21:29

jcomeau_ictx

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Using python 3.4: `json.dump(dict(),io.StringIO(),encoding='utf-8')` gives me: `TypeError: __init__() got an unexpected keyword argument 'encoding'` – Jean-François Fabre Jan 16 '17 at 21:48
the question is tagged python2.7 – jcomeau_ictx Jan 16 '17 at 22:38

Python: encoding a file as you write it

1 Answers1