old_contents: import unittest
  from tip.algorithms.sorting.mergesort import mergesort
  
  
  class TestMergesort(unittest.TestCase):
  
      def test_mergesort_basic(self):
          unsorted_list = [5, 3, 7, 8, 9, 3]
          sorted_list = mergesort(unsorted_list)
          self.assertEqual(sorted_list, sorted(unsorted_list))
  
      def test_mergesort_trivial(self):
          unsorted_list = [1]
          sorted_list = mergesort(unsorted_list)
          self.assertEqual(sorted_list, sorted(unsorted_list))
  
      def test_mergesort_with_duplicates(self):
          unsorted_list = [1, 1, 1, 1]
          sorted_list = mergesort(unsorted_list)
          self.assertEqual(sorted_list, sorted(unsorted_list))
  
      def test_mergesort_with_empty_list(self):
          unsorted_list = []
          sorted_list = mergesort(unsorted_list)
          self.assertEqual(sorted_list, sorted(unsorted_list))
  
new_contents: from tip.algorithms.sorting.mergesort import mergesort
  
  
  class TestMergesort():
      """Test class for Merge Sort algorithm."""
  
      def test_mergesort_basic(self):
          """Test basic sorting."""
          unsorted_list = [5, 3, 7, 8, 9, 3]
          sorted_list = mergesort(unsorted_list)
          assert sorted_list == sorted(unsorted_list)
  
      def test_mergesort_trivial(self):
          """Test sorting when it's only one item."""
          unsorted_list = [1]
          sorted_list = mergesort(unsorted_list)
          assert sorted_list == sorted(unsorted_list)
  
      def test_mergesort_with_duplicates(self):
          """Test sorting a list with duplicates."""
          unsorted_list = [1, 1, 1, 1]
          sorted_list = mergesort(unsorted_list)
          assert sorted_list == sorted(unsorted_list)
  
      def test_mergesort_with_empty_list(self):
          """Test sorting a empty list."""
          unsorted_list = []
          sorted_list = mergesort(unsorted_list)
          assert sorted_list == sorted(unsorted_list)
  
subject: Remove unittest requirement