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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 _parse_json(self, jstring=None):
 """Parse jstring and return a Python data structure. 'jstring' a string of JSON. May not be None. Returns a Python data structure. If jstring couldn't be parsed, raises an APIDataException."""


        # Argument error checking.
        assert jstring is not None

        result = None

        try:
            result = json.loads(jstring)
        except (ValueError) as exception:
            msg = 'Unable to convert JSON string to Python data structure.'
            raise APIDataException(exception, jstring, msg)

        return result