diff --git a/stdlib/3/stat.pyi b/stdlib/3/stat.pyi
index 374373f84..60600ed53 100644
--- a/stdlib/3/stat.pyi
+++ b/stdlib/3/stat.pyi
@@ -14,7 +14,7 @@ def S_ISLNK(mode: int) -> bool: ...
 def S_ISSOCK(mode: int) -> bool: ...
 
 def S_IMODE(mode: int) -> int: ...
-def S_IFMT(mode) -> int: ...
+def S_IFMT(mode: int) -> int: ...
 
 ST_MODE = 0
 ST_INO = 0