[docs] [issue34713] csvwriter.writerow()'s return type is undocumented

[Nicholas Chammas]

Nicholas Chammas <nicholas.chammas at gmail.com> added the comment:

Looks like it's bytes written, not characters:

```
>>> import csv
>>> with open('test.csv', 'w', newline='') as csv_file:
...     csv_writer = csv.writer(
...         csv_file,
...         dialect='unix',
...     )
...     csv_writer.writerow('야 너')  # 3 characters
... 
12
```

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue34713>
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