Hi,

Attempting completion when point is before the last prompt in the
Python Shell buffer causes an Invalid search bound error:

1. emacs -Q
2. M-x run-python
3. Make sure the prompt is displayed.
4. C-p (M-x previous-line)
5. TAB (M-x python-shell-completion-complete-or-indent)

Attached is a patch to fix this issue.  "No match" will be displayed
when completion is attempted and point is before the last prompt.

Best Regards,

--

In GNU Emacs 29.0.50 (build 7, x86_64-pc-linux-gnu, X toolkit, cairo
 version 1.16.0, Xaw scroll bars) of 2022-10-15 built on ubuntu
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