chip of slitless spectoscory rotate 1 deg around chip center, add these feature to code

    cd_rot = np.dot(mat, cd)

    return cd_rot

def calcaluteSLSRotSkyCoor(pix_xy = None,rot_angle = 1, xlen = 9216, ylen = 9232, w = None):

    rad = np.deg2rad(rot_angle)

    mat = np.zeros((2,2))

    mat[0,:] = np.array([np.cos(rad),-np.sin(rad)])

    mat[1,:] = np.array([np.sin(rad),np.cos(rad)])

    center = np.array([xlen/2, ylen/2])

    rot_pix = np.dot(mat, pix_xy-center) + center

    skyCoor = w.wcs_pix2world(np.array([rot_pix]), 1)

    return skyCoor

# def Header_extention(xlen = 9216, ylen = 9232, gain = 1.0, readout = 5.0, dark = 0.02,saturation=90000, row_num = 1, col_num = 1):

#

##9232 9216  898 534 1309 60 -40  -23.4333

def WCS_def(xlen = 9216, ylen = 9232, gapy = 898.0, gapx1 = 534, gapx2 = 1309, ra = 60, dec = -40, pa = -23.433,psize = 0.074, row_num = 1, col_num = 1):

def WCS_def(xlen = 9216, ylen = 9232, gapy = 898.0, gapx1 = 534, gapx2 = 1309, ra = 60, dec = -40, pa = -23.433,psize = 0.074, row_num = 1, col_num = 1, filter = 'GI'):

    """ Creat a wcs frame for CCST with multiple extensions

        r_dat['CD1_2'] = cd_rot[0,1]

        r_dat['CD2_1'] = cd_rot[1,0]

        r_dat['CD2_2'] = cd_rot[1,1]

        if filter in ['GU', 'GV', 'GI']:

            from astropy import wcs

            w = wcs.WCS(naxis=2)

            w.wcs.crpix = [r_dat['CRPIX1'], r_dat['CRPIX2']]

            w.wcs.cd = cd_rot

            w.wcs.crval = [ra_ref, dec_ref]

            w.wcs.ctype = [r_dat['CTYPE1'], r_dat['CTYPE2']]

            # test_center_o = w.wcs_pix2world(np.array([[xlen / 2, ylen / 2]]), 1)

            sls_rot = 1

            if i > 2:

                sls_rot = -sls_rot

            sn_x = 30

            sn_y = 30

            x_pixs = np.zeros(sn_y * sn_x)

            y_pixs = np.zeros(sn_y * sn_x)

            xpixs_line = np.linspace(1, xlen, sn_x)

            ypixs_line = np.linspace(1, ylen, sn_y)

            sky_coors = []

            for n1, y in enumerate(ypixs_line):

                for n2, x in enumerate(xpixs_line):

                    i_pix = n1 * sn_x + n2

                    x_pixs[i_pix] = x

                    y_pixs[i_pix] = y

                    pix_coor = np.array([x, y])

                    sc1 = calcaluteSLSRotSkyCoor(pix_xy=pix_coor, rot_angle=sls_rot, w=w)

                    # print(sc1[0,0],sc1[0,1])

                    sky_coors.append((sc1[0, 0], sc1[0, 1]))

            from astropy.coordinates import SkyCoord

            from astropy.wcs.utils import fit_wcs_from_points

            wcs_new = fit_wcs_from_points(xy=np.array([x_pixs, y_pixs]),

                                          world_coords=SkyCoord(sky_coors, frame="icrs", unit="deg"), projection='TAN')

            # print(wcs_new)

            # test_center = wcs_new.wcs_pix2world(np.array([[xlen / 2, ylen / 2]]), 1)

            #

            # print(test_center - test_center_o)

            r_dat['CD1_1'] = wcs_new.wcs.cd[0, 0]

            r_dat['CD1_2'] = wcs_new.wcs.cd[0, 1]

            r_dat['CD2_1'] = wcs_new.wcs.cd[1, 0]

            r_dat['CD2_2'] = wcs_new.wcs.cd[1, 1]

            r_dat['CRPIX1'] = wcs_new.wcs.crpix[0]

            r_dat['CRPIX2'] = wcs_new.wcs.crpix[1]

            r_dat['CRVAL1'] = wcs_new.wcs.crval[0]

            r_dat['CRVAL2'] = wcs_new.wcs.crval[1]

        return r_dat

    h_ext['CCDCHIP'] =  'ccd' + CCDID[k-1].rjust(2,'0')

    h_ext['POS_ANG'] = pa

    header_wcs = WCS_def(xlen=xlen, ylen=ylen, gapy=898.0, gapx1=534, gapx2=1309, ra=ra, dec=dec, pa=pa, psize=psize,

                         row_num=row_num, col_num=col_num)

                         row_num=row_num, col_num=col_num, filter = h_ext['FILTER'])

    h_ext['CRPIX1'] = header_wcs['CRPIX1']

    h_ext['CRPIX2'] = header_wcs['CRPIX2']