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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 __get_dbms_version(self, make_connection=True):
 """ Returns the 'DBMS Version' string, or ''. If a connection to the database has not already been established, a connection will be made when `make_connection` is True. """

        if not self.connection and make_connection:
            self.connect()
        with self.connection.cursor() as cursor:
            cursor.execute("SELECT SERVERPROPERTY('productversion')")
            return cursor.fetchone()[0]