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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_current_thumbnail(self, thumbnail):
 """Set the currently selected thumbnail."""

        self.current_thumbnail = thumbnail
        self.figure_viewer.load_figure(
                thumbnail.canvas.fig, thumbnail.canvas.fmt)
        for thumbnail in self._thumbnails:
            thumbnail.highlight_canvas(thumbnail == self.current_thumbnail)