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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_selection(self, star):
 """This method is called when the user clicks on a plotted star in the fitsviewer. """

        try:
            # NOTE: this works around a quirk of Qt widget set where
            # selecting programatically in the table triggers the widget
            # selection callback (see select_star_cb() in Catalogs.py for Qt)
            self._select_flag = True
            self.mark_selection(star)

        finally:
            self._select_flag = False