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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 _get_dotgraphs(self, hdrgo, usrgos, pltargs, go2parentids):
 """Get a GO DAG in a dot-language string for a single Group of user GOs."""

        gosubdagplotnts = self._get_gosubdagplotnts(hdrgo, usrgos, pltargs, go2parentids)
        # Create DAG graphs as dot language strings. Loop through GoSubDagPlotNt list
        dotstrs = [obj.get_dotstr() for obj in gosubdagplotnts]
        return dotstrs