old_contents: import unittest
  from src import conversion
  
  class TestNotationConverter(unittest.TestCase):
      """Tests for NotationConverter class"""
      def test_alg_search_good_input_a5(self):
          """Input with 'a5'"""
          actual_result = main.TileLine('w').line
          expected_result = '       '
          self.assertEqual(actual_result, expected_result)
new_contents: """Tests for conversion module"""
  
  import unittest
  from src import conversion
  
  class TestNotationConverter(unittest.TestCase):
      """Tests for NotationConverter class"""
      def test_alg_search_good_input_a5(self):
          """Input with 'a5'"""
          n_con = conversion.NotationConverter()
          actual_result = n_con.alg_search('a5')
          expected_result = ('a5', 'qr5', 'qr4')
          self.assertEqual(actual_result, expected_result)
  
      def test_alg_search_good_input_f7(self):
          """Input with 'f7'"""
          n_con = conversion.NotationConverter()
          actual_result = n_con.alg_search('f7')
          expected_result = ('f7', 'kb7', 'kb2')
          self.assertEqual(actual_result, expected_result)
  
      def test_alg_search_nonexistant(self):
          """Input which does not exist"""
          n_con = conversion.NotationConverter()
          self.assertRaises(LookupError, n_con.alg_search, 'f99')
  
      def test_desc_search_good_white(self):
          """Input with good value"""
          n_con = conversion.NotationConverter()
          actual_result = n_con.desc_search('qn3', 'white')
          expected_result = ('b3', 'qn3', 'qn6')
          self.assertEqual(actual_result, expected_result)
  
      def test_desc_search_good_black(self):
          """Input with good value"""
          n_con = conversion.NotationConverter()
          actual_result = n_con.desc_search('qn6', 'black')
          expected_result = ('b3', 'qn3', 'qn6')
          self.assertEqual(actual_result, expected_result)
  
      def test_desc_search_nonexistant(self):
          """Input with good value"""
          n_con = conversion.NotationConverter()
          self.assertRaises(LookupError, n_con.desc_search, 'qn333', 'white')
  
subject: Add tests for NotationConverter methods