Need help with End biome generation

theres 3 issues here. first, you forgot some commas, so that'll always cause it to return an error. second, you repeated the entire "surface_rule" line, but each biome sequence is supposed to be in the "sequence": [ ] bracket. and finally, the biomes have to be the vanilla biomes, since this method utilizes and rearranges the vanilla end sub-biomes. more biomes can be added, but would require further modification of the end's biome distribution, which in turn would make the main island use the biome generation of the outer end islands instead of the main islands normal biome "the_end". the Alternate End dimension in my End Update mod uses this more extensive method.