diff --git a/Lib/contextlib.py b/Lib/contextlib.py
index a0b523c96fb285..eb5946145b47ee 100644
--- a/Lib/contextlib.py
+++ b/Lib/contextlib.py
@@ -9,7 +9,7 @@
 __all__ = ["asynccontextmanager", "contextmanager", "closing", "nullcontext",
            "AbstractContextManager", "AbstractAsyncContextManager",
            "AsyncExitStack", "ContextDecorator", "ExitStack",
-           "redirect_stdout", "redirect_stderr", "suppress"]
+           "redirect_stdout", "redirect_stderr", "suppress", "aclosing"]
 
 
 class AbstractContextManager(abc.ABC):