In my example, the first half of the program is simply a switch to allow manual selection of the backend to use from the command-line.

在我的示例中，该程序的上半部分完全是实现一个switch，允许从命令行手工选择要使用的后端。

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Thanks to ActiveSelect, this modern automatic transmission also offers manual gear selection, as well as the choice of a winter driving program.

由于解放油罐车也提供了现代自动变速器齿轮选择手册，以及选择的一个冬天的驱动程序。

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