Tidy up tests

tests/test_models.py

@@ -46,7 +46,7 @@ class TestMMModels(unittest.TestCase):
     def test_track_repr(self):
         with db.Session() as session:
             session.add(self.track1)
-            _ =str(self.track1)
+            _ = str(self.track1)
 
     def test_notecolours_get_colour(self):
         """Create a colour record and retrieve all colours"""

tests/test_playlists.py

@@ -1,5 +1,4 @@
 # Standard library imports
-import datetime as dt
 import os
 import unittest
 
@@ -64,12 +63,6 @@ class MyTestCase(unittest.TestCase):
     def down(self):
         db.drop_all()
 
-    # @with_updown
-    # def test_some_property(self):
-    #     with self.qtbot.waitSignal(self.widget.my_signal, timeout=300):
-    #         self.widget.do_thing()
-    #     self.assertEqual(self.widget.get_thing(), 'foo')
-
     @with_updown
     def test_init(self):
         """Just check we can create a playlist_tab"""