class_docstr: Dataset for test data in OGBL-WikiKG2
  
  Args:
      triplets (dict):
          The collections of test data with keys 'h', 'r',
          't', 'candaidate_h' and 'candidate_t'.
          The values of 'h', 'r' and 't' are 1D np.ndarray.
          The values of 'candidate_*' are 2d np.ndarray.
class_docstr_tok: ["Dataset","for","test","data","in","OGBL-WikiKG2","Args",":","triplets","(","dict",")",":","The","collections","of","test","data","with","keys","'","h","'",",","'","r","'",",","'t","'",",","'candaidate_h","'","and","'candidate_t","'",".","The","values","of","'","h","'",",","'","r","'","and","'t","'","are","1D","np.ndarray",".","The","values","of","'candidate_","*","'","are","2d","np.ndarray","."]
code: def __getitem__(self, index):
      h = self._h[index]
      r = self._r[index]
      t = self._t[index]
      neg_head = self._neg_head[index]
      neg_tail = self._neg_tail[index]
      return h, r, t, neg_head, neg_tail
  
imports: import os
  import numpy
  from numpy.random import default_rng
  import paddle
  from paddle.io import Dataset
  from paddle.io import DataLoader, DistributedBatchSampler
  from utils import timer_wrapper
label_desc: Use image node_id 3 for calling the TestWikiKG2 obj's underlying member method code with example usage: obj.__getitem__(index) and returns: h,  r,  t,  neg_head,  neg_tail