diff --git a/openlp/plugins/songs/forms/duplicatesongremovalform.py b/openlp/plugins/songs/forms/duplicatesongremovalform.py
index 54778de03..d63391c08 100644
--- a/openlp/plugins/songs/forms/duplicatesongremovalform.py
+++ b/openlp/plugins/songs/forms/duplicatesongremovalform.py
@@ -48,7 +48,8 @@ log = logging.getLogger(__name__)
 
 class SongIterator(object):
     """
-    This class implements an iterator for the song duplicate finder. The iterator returns a tuple of two songs.
+    This class implements an iterator for the song duplicate finder. The iterator returns a tuple of two songs. When
+    completely iterated then all songs have once been returned combined with any other songs.
     """
     def __init__(self, songs):
         self.songs = songs
diff --git a/tests/functional/openlp_plugins/songs/test_lib.py b/tests/functional/openlp_plugins/songs/test_lib.py
index beff6d0d5..2683770c6 100644
--- a/tests/functional/openlp_plugins/songs/test_lib.py
+++ b/tests/functional/openlp_plugins/songs/test_lib.py
@@ -96,10 +96,10 @@ class TestLib(TestCase):
         self.song2.search_lyrics = self.full_lyrics
 
         # WHEN: We compare those songs for equality.
-        result = songs_probably_equal(self.song1, self.song2)
+        result = songs_probably_equal((self.song1, self.song2))
 
         # THEN: The result should be True.
-        assert result == True, 'The result should be True'
+        assert result == (self.song1, self.song2), 'The result should be the tuble of songs'
 
     def songs_probably_equal_short_song_test(self):
         """
@@ -110,10 +110,10 @@ class TestLib(TestCase):
         self.song2.search_lyrics = self.short_lyrics
 
         # WHEN: We compare those songs for equality.
-        result = songs_probably_equal(self.song1, self.song2)
+        result = songs_probably_equal((self.song1, self.song2))
 
         # THEN: The result should be True.
-        assert result == True, 'The result should be True'
+        assert result == (self.song1, self.song2), 'The result should be the tuble of songs'
 
     def songs_probably_equal_error_song_test(self):
         """
@@ -124,10 +124,10 @@ class TestLib(TestCase):
         self.song2.search_lyrics = self.error_lyrics
 
         # WHEN: We compare those songs for equality.
-        result = songs_probably_equal(self.song1, self.song2)
+        result = songs_probably_equal((self.song1, self.song2))
 
         # THEN: The result should be True.
-        assert result == True, 'The result should be True'
+        assert result == (self.song1, self.song2), 'The result should be the tuble of songs'
 
     def songs_probably_equal_different_song_test(self):
         """
@@ -138,10 +138,10 @@ class TestLib(TestCase):
         self.song2.search_lyrics = self.different_lyrics
 
         # WHEN: We compare those songs for equality.
-        result = songs_probably_equal(self.song1, self.song2)
+        result = songs_probably_equal((self.song1, self.song2))
 
         # THEN: The result should be False.
-        assert result == False, 'The result should be False'
+        assert result is None, 'The result should be None'
 
     def remove_typos_beginning_test(self):
         """