old_contents: import unittest
  
  from src.randomized_selection import randomized_selection
  
  
  class RandomizedSelection(unittest.TestCase):
  
      def test_randomized_selection(self):
          arr = [10, 8, 2, 4]
          actual = randomized_selection(arr, len(arr), 2)
          expected = 8
          self.assertEqual(actual, expected, 'should select the third position')
  
new_contents: import unittest
  
  from src.randomized_selection import randomized_selection
  
  
  class RandomizedSelection(unittest.TestCase):
  
      def test_randomized_selection(self):
          arr = [10, 8, 2, 4]
          actual = randomized_selection(arr, len(arr), 2)
          expected = 8
          self.assertEqual(actual, expected, 'should select the third position')
  
      def test_randomized_selection_to_produce_median(self):
          arr = [8,2,1,7,4,5,3,0,6,9]
          actual = randomized_selection(arr, len(arr), 5)
          expected = 5
          self.assertEqual(actual, expected, 'should produce the arrays median')
  
subject: add test to produce median of an array