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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 _button_plus_clicked(self, n):
 """ Create a new colorpoint. """

        self._button_save.setEnabled(True)

        self.insert_colorpoint(self._colorpoint_list[n][0],
                               self._colorpoint_list[n][1],
                               self._colorpoint_list[n][2])
        self._build_gui()