code: def set_ref_batch(self, ref_batch):
      with bf.BlobFile(ref_batch, "rb") as f:
          data = np.load(f)
          fid_stats = FIDStatistics(
              mu=data["mu"], sigma=data["sigma"], resolution=-1
          )
          spatial_stats = FIDStatistics(
              mu=data["mu_s"], sigma=data["sigma_s"], resolution=-1
          )
          clip_stats = FIDStatistics(
              mu=data["mu_clip"],
              sigma=data["sigma_clip"],
              resolution=-1,
          )
  
      self.ref_features[ref_batch] = (
          fid_stats,
          spatial_stats,
          clip_stats,
      )
  
imports: from .inception_v3 import InceptionV3
  import blobfile
  import torch
  import torch.distributed
  import torch.nn
  from cm import dist_util
  import numpy
  import warnings
  from scipy import linalg
  from PIL import Image
  from tqdm import tqdm
label_desc: Use image node_id 8 for calling the FIDAndIS obj's underlying member method code with example usage: obj.set_ref_batch(ref_batch) without return types