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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 _send_output(self, message_body=None):
 """Send the currently buffered request and clear the buffer. Appends an extra \\r\\n to the buffer. A message_body may be specified, to be appended to the request. """

        self._buffer.extend((bytes(b""), bytes(b"")))
        msg = bytes(b"\r\n").join(self._buffer)
        del self._buffer[:]
        # If msg and message_body are sent in a single send() call,
        # it will avoid performance problems caused by the interaction
        # between delayed ack and the Nagle algorithm.
        if isinstance(message_body, bytes):
            msg += message_body
            message_body = None
        self.send(msg)
        if message_body is not None:
            # message_body was not a string (i.e. it is a file), and
            # we must run the risk of Nagle.
            self.send(message_body)