Add missing return type declaration

diff --git a/mkosi/sandbox/__init__.py b/mkosi/sandbox/__init__.py
index 7db340c5284903e9ea87715f196d6d7b47b51cd9..d42d556de544c70e694ef0974ef085d1b8b09a4d 100644 (file)
--- a/mkosi/sandbox/__init__.py
+++ b/mkosi/sandbox/__init__.py
@@ -254,7 +254,7 @@ def mount_rbind(src: str, dst: str, attrs: int = 0) -> None:
 
 
 class umask:
-    def __init__(self, mask: int):
+    def __init__(self, mask: int) -> None:
         self.mask = mask
 
     def __enter__(self) -> None: