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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 shift_display(self, amount):
 """Shift the display. Use negative amounts to shift left and positive amounts to shift right."""

        if amount == 0:
            return
        direction = c.LCD_MOVERIGHT if amount > 0 else c.LCD_MOVELEFT
        for i in range(abs(amount)):
            self.command(c.LCD_CURSORSHIFT | c.LCD_DISPLAYMOVE | direction)
            c.usleep(50)