code: def setUpClass(cls):
      cls.x = np.random.normal(100, 50, (91, 4))
  
imports: import logging
  import unittest
  from functools import partial
  import numpy
  from scipy.spatial.distance import squareform, pdist
  from sklearn import datasets
  from sklearn.model_selection import train_test_split
  from openTSNE import affinity, nearest_neighbors
label_desc: Use image node_id 1 for calling the TestPerplexityBased obj's underlying member method code with example usage: obj.setUpClass(cls) without return types