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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 show_highlight(self, artist):
 """Show or create a highlight for a givent artist."""

        # This is a separate method to make subclassing easier.
        if artist in self.highlights:
            self.highlights[artist].set_visible(True)
        else:
            self.highlights[artist] = self.create_highlight(artist)
        return self.highlights[artist]