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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 close(self):
 """Close the SocketIO object. This doesn't close the underlying socket, except if all references to it have disappeared. """

        if self.closed:
            return
        io.RawIOBase.close(self)
        self._sock._decref_socketios()
        self._sock = None