docstr: Relation feature
  - np.ndarray of shape (num_relations, num_feat_dims)
    i-th row stores the feature of i-th relation
    * saved in np.float16
docstr_tok: ["Relation","feature","-","np.ndarray","of","shape","(","num_relations",",","num_feat_dims",")","i-th","row","stores","the","feature","of","i-th","relation","*","saved","in","np.float16"]
code: def relation_feat(self) -> np.ndarray:
      """
      Relation feature
      - np.ndarray of shape (num_relations, num_feat_dims)
        i-th row stores the feature of i-th relation
        * saved in np.float16
      """
      if self._relation_feat is None:
          path = osp.join(self.processed_dir, "relation_feat.npy")
          self._relation_feat = np.load(path)
      return self._relation_feat
  
imports: from typing import Optional, Union, Dict
  import os
  import shutil
  import os.path
  import torch
  import numpy
  import pandas
  from ogb.utils.url import decide_download, download_url, extract_zip, makedirs
label_desc: Use image node_id 8 for calling the WikiKG90MDataset obj's underlying member method code with example usage: obj.relation_feat() and returns: self