code: def test_distance(self):
      self.assertAlmostEqual(distance((1, 2, 3), (1, 0, -1)), 4.47, 2)
  
imports: from algorithms.ml.nearest_neighbor import distance, nearest_neighbor
  import unittest
label_desc: Use image node_id 3 for calling the TestML obj's underlying member method code with example usage: obj.test_distance() without return types