diff --git a/scalene/replacement_sem_lock.py b/scalene/replacement_sem_lock.py
index 67648a02c..44a741695 100644
--- a/scalene/replacement_sem_lock.py
+++ b/scalene/replacement_sem_lock.py
@@ -30,4 +30,4 @@ def __exit__(self, *args: Any) -> None:
         super().__exit__(*args)
 
     def __reduce__(self) -> Tuple[Callable[[], ReplacementSemLock], Tuple[()]]:
-        return (lambda: ReplacementSemLock(), ())
+        return (ReplacementSemLock, ())