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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 write_fits(self, fitsfile):
 """Write the ROI model to a FITS file."""


        tab = self.create_table()
        hdu_data = fits.table_to_hdu(tab)
        hdus = [fits.PrimaryHDU(), hdu_data]
        fits_utils.write_hdus(hdus, fitsfile)