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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 slaveof(self, host, port=None):
 """Make the server a slave of another instance, or promote it as master. Calling ``slaveof(None)`` will send ``SLAVEOF NO ONE``. .. versionchanged:: v0.2.6 ``slaveof()`` form deprecated in favour of explicit ``slaveof(None)``. """

        if host is None and port is None:
            return self.execute(b'SLAVEOF', b'NO', b'ONE')
        return self.execute(b'SLAVEOF', host, port)