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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 clear_widget(self):
 """ Clears the thumbnail display widget of all thumbnails, but does not remove them from the thumb_dict or thumb_list. """

        if not self.gui_up:
            return
        canvas = self.c_view.get_canvas()
        canvas.delete_all_objects()
        self.c_view.redraw(whence=0)