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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 unwrap(self):
 """Remove the security layer. Use this method only if you want to send plaintext data on the connection after the security layer has been removed. In all other cases, use :meth:`close`. If the unwrap is initiated by us, then any data sent after it will be buffered until the corresponding close_notify response is received from our peer. If the unwrap is initiated by the remote peer, then this method will acknowledge it. You need an application level protocol to determine when to do this because the receipt of a close_notify is not communicated to the application. """

        if self._error:
            raise compat.saved_exc(self._error)
        elif self._closing or self._handle.closed:
            raise TransportError('SSL transport is closing/closed')
        self._close_on_unwrap = False
        self._write_backlog.append([b'', False])
        self._process_write_backlog()