Petri Lehtinen added the comment:
It may also be unicode if the encoding parameter is used even if there are no unicode objects in the input.
>>> json.dumps([u'Ş'.encode('iso-8859-9')], encoding='iso-8859-9', ensure_ascii=False)
u'["\u015e"]'
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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue13769>
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