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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:
 async def down(self):
 """Press key down."""

        await self._send_commands(
            self._move('Down', 0, 20, 250),
            self._move('Move', 1, 20, 255),
            self._move('Move', 2, 20, 260),
            self._move('Move', 3, 20, 265),
            self._move('Move', 4, 20, 270),
            self._move('Move', 5, 20, 275),
            self._move('Up', 6, 20, 275))