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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 disconnect(self):
 """ Disconnects from the SSDB server """

        self._parser.on_disconnect()
        if self._sock is None:
            return
        try:
            self._sock.shutdown(socket.SHUT_RDWR)
            self._sock.close()
        except socket.error:
            pass
        self._sock = None