[3.11] gh-112165: Fix typo in `__main__.py` (GH-112183) (#112185)

gh-112165: Fix typo in `__main__.py` (GH-112183)

Change '[2]' to '[1]' to get second argument.
(cherry picked from commit 8cd70eefc7f3363cfa0d43f34522c3072fa9e160)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>