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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 sscan(self, key, cursor=0, match=None, count=None):
 """Incrementally iterate Set elements."""

        tokens = [key, cursor]
        match is not None and tokens.extend([b'MATCH', match])
        count is not None and tokens.extend([b'COUNT', count])
        fut = self.execute(b'SSCAN', *tokens)
        return wait_convert(fut, lambda obj: (int(obj[0]), obj[1]))