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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, size=None):
 # pylint: disable=invalid-name """Reads from the buffer."""

        if size is None or size < 0:
            raise exceptions.NotYetImplementedError(
                'Illegal read of size %s requested on BufferedStream. '
                'Wrapped stream %s is at position %s-%s, '
                '%s bytes remaining.' %
                (size, self.__stream, self.__start_pos, self.__end_pos,
                 self._bytes_remaining))

        data = ''
        if self._bytes_remaining:
            size = min(size, self._bytes_remaining)
            data = self.__buffered_data[
                self.__buffer_pos:self.__buffer_pos + size]
            self.__buffer_pos += size
        return data