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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def list_data(self):
 """ Return all the data stored in the autocomplete index. If the data was stored as serialized JSON, then it will be de-serialized before being returned. :rtype: list """

        fn = (lambda v: json.loads(decode(v))) if self._use_json else decode
        return map(fn, self._data.values())