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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 to_json_str(self):
 """Convert data to json string representation. Returns: json representation as string. """

    _json = self.to_json()
    try:
      return json.dumps(_json, sort_keys=True, cls=JsonEncoder)
    except:
      logging.exception("Could not serialize JSON: %r", _json)
      raise