How to use the cson.createJSONString function in cson

Details: error,
            Errors: [{
                Message: error,
                FileName: sourceFileName
            }]
        }));
        writer.end();
        return;
    }

    writer.write(JSON.stringify({
        Success: true,
        SourceFileName: sourceFileName,
        TargetFileName: targetFileName,
        Remarks: "Successful!",
        Content: CSON.createJSONString(data)
    }));
    writer.end();
};

return new Promise((resolve, reject) => {
    cson.createJSONString(body, (err, str) => {
      if (err) return reject(err);
      resolve(str);
    });
  });
};