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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 _simpleQuery(self, query):
 """Executes simple query which returns a single column. @param query: Query string. @return: Query result string. """

        cur = self._conn.cursor()
        cur.execute(query)
        row = cur.fetchone()
        return util.parse_value(row[0])