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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 _setns(self, value):
 """ Set the default repository namespace to be used. This method exists for compatibility. Use the :attr:`default_namespace` property instead. """

        if self.conn is not None:
            self.conn.default_namespace = value
        else:
            self.__default_namespace = value