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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 set_display(self, index=None):
 """Show an image on the display."""

        # pylint: disable=no-member
        if index:
            image = self.microbit.Image.STD_IMAGES[index]
        else:
            image = self.default_image
        self.microbit.display.show(image)