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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 facet_raw(self, **kw):
 """ Return a new S instance with raw facet args combined with existing set. """

        items = kw.items()
        if six.PY3:
            items = list(items)
        return self._clone(next_step=('facet_raw', items))