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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 open_addnew_win(self, *args, **kwargs):
 """Open a new window so the use can choose to add new reftracks :returns: None :rtype: None :raises: NotImplementedError """

        if self.reftrackadderwin:
            self.reftrackadderwin.close()
        self.reftrackadderwin = ReftrackAdderWin(self.refobjinter, self.root, parent=self)
        self.reftrackadderwin.destroyed.connect(self.addnewwin_destroyed)
        self.reftrackadderwin.show()