diff --git a/git/cmd.py b/git/cmd.py
index 6354da666..c37d28988 100644
--- a/git/cmd.py
+++ b/git/cmd.py
@@ -278,6 +278,8 @@ def _safer_popen_windows(
         )
 
 
+safer_popen: Callable[..., Popen]
+
 if os.name == "nt":
     safer_popen = _safer_popen_windows
 else: