diff --git a/anki/models.py b/anki/models.py
index c32ae0be2..310a1a0fc 100644
--- a/anki/models.py
+++ b/anki/models.py
@@ -240,7 +240,7 @@ and notes.mid = ? and cards.ord = ?""", m['id'], ord)
         return m['sortf']
 
     def setSortIdx(self, m, idx):
-        assert idx >= 0 and idx < len(m['flds'])
+        assert 0 <= idx < len(m['flds'])
         self.col.modSchema(check=True)
         m['sortf'] = idx
         self.col.updateFieldCache(self.nids(m))
diff --git a/anki/sched.py b/anki/sched.py
index 5e9a8b22f..be6242b85 100644
--- a/anki/sched.py
+++ b/anki/sched.py
@@ -56,7 +56,7 @@ class Scheduler:
 
     def answerCard(self, card, ease):
         self.col.log()
-        assert ease >= 1 and ease <= 4
+        assert 1 <= ease <= 4
         self.col.markReview(card)
         if self._burySiblingsOnAnswer:
             self._burySiblings(card)