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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_sortgo(self):
 """Get function for sorting GO terms in a list of namedtuples."""

        if 'sortgo' in self.datobj.kws:
            return self.datobj.kws['sortgo']
        return self.datobj.grprdflt.gosubdag.prt_attr['sort'] + "\n"