481     class JSString(str):

   482         """use this string sub class in values given to :func:`js_dumps` to

   483         insert raw javascript chain in some JSON string

   484         """

   485 

   486     def _dict2js(d, predictable=False):

   487         res = [key + ': ' + js_dumps(val, predictable)

   488                for key, val in d.iteritems()]

   489         return '{%s}' % ', '.join(res)

   490 

   491     def _list2js(l, predictable=False):

   492         return '[%s]' % ', '.join([js_dumps(val, predictable) for val in l])

   493 

   494     def js_dumps(something, predictable=False):

   495         """similar as :func:`json_dumps`, except values which are instances of

   496         :class:`JSString` are expected to be valid javascript and will be output

   497         as is

   498 

   499         >>> js_dumps({'hop': JSString('$.hop'), 'bar': None}, predictable=True)

   500         '{bar: null, hop: $.hop}'

   501         >>> js_dumps({'hop': '$.hop'})

   502         '{hop: "$.hop"}'

   503         >>> js_dumps({'hip': {'hop': JSString('momo')}})

   504         '{hip: {hop: momo}}'

   505         """

   506         if isinstance(something, dict):

   507             return _dict2js(something, predictable)

   508         if isinstance(something, list):

   509             return _list2js(something, predictable)

   510         if isinstance(something, JSString):

   511             return something

   512         return json_dumps(something)

   513 

   514