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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 define_from_header(cls, image_header):
 """Define class members directly from FITS header. Parameters image_header : instance of hdulist.header Header content from a FITS file. """


        self = CsuConfiguration()

        # declare lists to store configuration of CSU bars
        self._csu_bar_left = []
        self._csu_bar_right = []
        self._csu_bar_slit_center = []
        self._csu_bar_slit_width = []

        for i in range(EMIR_NBARS):
            ibar = i + 1
            keyword = 'CSUP{}'.format(ibar)
            if keyword in image_header:
                self._csu_bar_left.append(image_header[keyword])
            else:
                raise ValueError("Expected keyword " + keyword + " not found!")
            keyword = 'CSUP{}'.format(ibar + EMIR_NBARS)
            if keyword in image_header:
                # set the same origin as the one employed for _csu_bar_left
                self._csu_bar_right.append(341.5 - image_header[keyword])
            else:
                raise ValueError("Expected keyword " + keyword + " not found!")
            self._csu_bar_slit_center.append(
                (self._csu_bar_left[i] + self._csu_bar_right[i]) / 2
            )
            self._csu_bar_slit_width.append(
                self._csu_bar_right[i] - self._csu_bar_left[i]
            )

        return self