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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 get_index_list(nside, nest, region):
 """ Returns the list of pixels indices for all the pixels in a region nside : HEALPix nside parameter nest : True for 'NESTED', False = 'RING' region : HEALPix region string """


        tokens = parse_hpxregion(region)
        if tokens[0] == 'DISK':
            vec = coords_to_vec(float(tokens[1]), float(tokens[2]))
            ilist = hp.query_disc(nside, vec[0], np.radians(float(tokens[3])),
                                  inclusive=False, nest=nest)
        elif tokens[0] == 'DISK_INC':
            vec = coords_to_vec(float(tokens[1]), float(tokens[2]))
            ilist = hp.query_disc(nside, vec[0], np.radians(float(tokens[3])),
                                  inclusive=True, fact=int(tokens[4]),
                                  nest=nest)
        elif tokens[0] == 'HPX_PIXEL':
            nside_pix = int(tokens[2])
            if tokens[1] == 'NESTED':
                ipix_ring = hp.nest2ring(nside_pix, int(tokens[3]))
            elif tokens[1] == 'RING':
                ipix_ring = int(tokens[3])
            else:
                raise Exception(
                    "Did not recognize ordering scheme %s" % tokens[1])
            ilist = match_hpx_pixel(nside, nest, nside_pix, ipix_ring)
        else:
            raise Exception(
                "HPX.get_index_list did not recognize region type %s" % tokens[0])
        return ilist