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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 _plot_go_group(self, hdrgo, usrgos, pltargs, go2parentids):
 """Plot an exploratory GO DAG for a single Group of user GOs."""

        gosubdagplotnts = self._get_gosubdagplotnts(hdrgo, usrgos, pltargs, go2parentids)
        # Create pngs and return png names
        pngs = [obj.wrplt(pltargs.fout_dir, pltargs.plt_ext) for obj in gosubdagplotnts]
        return pngs