#17484: add tests for getpass.

Patch by Thomas Fenzl.
diff --git a/Lib/getpass.py b/Lib/getpass.py
index 53689e9..6ec6c788 100644
--- a/Lib/getpass.py
+++ b/Lib/getpass.py
@@ -40,6 +40,7 @@
     """
     fd = None
     tty = None
+    passwd = None
     try:
         # Always try reading and writing directly on the tty first.
         fd = os.open('/dev/tty', os.O_RDWR|os.O_NOCTTY)