Remove no longer necessary parts and add vae_file safeguard

    cache_enabled = shared.opts.sd_checkpoint_cache > 0

    if cache_enabled:

        sd_vae.restore_base_vae(model)

    vae_file = sd_vae.resolve_vae(checkpoint_file, vae_file=vae_file)

    if cache_enabled and checkpoint_info in checkpoints_loaded:

        # use checkpoint cache

        vae_name = sd_vae.get_filename(vae_file) if vae_file else None

        vae_message = f" with {vae_name} VAE" if vae_name else ""

        print(f"Loading weights [{sd_model_hash}]{vae_message} from cache")

        print(f"Loading weights [{sd_model_hash}] from cache")

        model.load_state_dict(checkpoints_loaded[checkpoint_info])

    else:

        # load from file

    model.sd_model_checkpoint = checkpoint_file

    model.sd_checkpoint_info = checkpoint_info

    vae_file = sd_vae.resolve_vae(checkpoint_file, vae_file=vae_file)

    sd_vae.load_vae(model, vae_file)

    # save_settings = False

    if vae_file:

        assert os.path.isfile(vae_file), f"VAE file doesn't exist: {vae_file}"

        print(f"Loading VAE weights from: {vae_file}")

        vae_ckpt = torch.load(vae_file, map_location=shared.weight_load_location)

        vae_dict_1 = {k: v for k, v in vae_ckpt["state_dict"].items() if k[0:4] != "loss" and k not in vae_ignore_keys}