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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 _init_kwelems(self):
 """Init set elements."""

        ret = set()
        if 'rcntobj' in self.kws:
            ret.add('dcnt')
            ret.add('D1')
        if 'tcntobj' in self.kws:
            ret.add('tcnt')
            ret.add('tfreq')
            ret.add('tinfo')
        return ret