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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_gosubdag(gosubdag=None):
 """Gets a GoSubDag initialized for use by a Grouper object."""

        if gosubdag is not None:
            if gosubdag.rcntobj is not None:
                return gosubdag
            else:
                gosubdag.init_auxobjs()
                return gosubdag
        else:
            go2obj = get_godag()
            return GoSubDag(None, go2obj, rcntobj=True)