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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 read(self, n=4096):
 """ Read up to `n` bytes of data from the Stream, after demuxing. Less than `n` bytes of data may be returned depending on the available payload, but the number of bytes returned will never exceed `n`. Because demuxing involves scanning 8-byte headers, the actual amount of data read from the underlying stream may be greater than `n`. """


        size = self._next_packet_size(n)

        if size <= 0:
            return
        else:
            data = six.binary_type()
            while len(data) < size:
                nxt = self.stream.read(size - len(data))
                if not nxt:
                    # the stream has closed, return what data we got
                    return data
                data = data + nxt
            return data