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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_to_fitsfile(self, fitsfile, clobber=True):
 """Write this mapping to a FITS file, to avoid having to recompute it """

        from fermipy.skymap import Map
        hpx_header = self._hpx.make_header()
        index_map = Map(self.ipixs, self.wcs)
        mult_map = Map(self.mult_val, self.wcs)
        prim_hdu = index_map.create_primary_hdu()
        mult_hdu = index_map.create_image_hdu()
        for key in ['COORDSYS', 'ORDERING', 'PIXTYPE',
                    'ORDERING', 'ORDER', 'NSIDE',
                    'FIRSTPIX', 'LASTPIX']:
            prim_hdu.header[key] = hpx_header[key]
            mult_hdu.header[key] = hpx_header[key]

        hdulist = fits.HDUList([prim_hdu, mult_hdu])
        hdulist.writeto(fitsfile, overwrite=clobber)