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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 abort(self):
 """ Abort the stream by writing an EOF if possible and closing the transport. The transport is closed using :meth:`asyncio.BaseTransport.close`, so buffered data is sent, but no more data will be received. The stream is in :attr:`State.CLOSED` state afterwards. This also works if the stream is currently closing, that is, waiting for the peer to send a stream footer. In that case, the stream will be closed locally as if the stream footer had been received. .. versionadded:: 0.5 """

        if self._smachine.state == State.CLOSED:
            return
        if self._smachine.state == State.READY:
            self._smachine.state = State.CLOSED
            return
        if (self._smachine.state != State.CLOSING and
                self._transport.can_write_eof()):
            self._transport.write_eof()
        self._close_transport()