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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 output(self, stream, disabletransferencoding = None):
 """ Set output stream and send response immediately """

        if self._sendHeaders:
            raise HttpProtocolException('Cannot modify response, headers already sent')
        self.outputstream = stream
        try:
            content_length = len(stream)
        except Exception:
            pass
        else:
            self.header(b'Content-Length', str(content_length).encode('ascii'))
        if disabletransferencoding is not None:
            self.disabledeflate = disabletransferencoding
        self._startResponse()