def pop_click(self,index=-<NUM_LIT:1>):
self.clicks.pop(index)<EOL>if self.show_clicks:<EOL><INDENT>mark = self.marks.pop(index)<EOL>mark.remove()<EOL>self.fig.canvas.draw()<EOL><DEDENT>
This removes a click from the list of clicks.  Defaults to
removing the last click.