I'm sorry, but I would like to revert my following fix:

"Enhance Python font-lock to support multilines"
commit 4915ca5dd4245a909c046e6691e8d4a1919890c8

I have found that there are performance issues when editing a large
file.  The issue can be reproduced as follows:

1. emacs -Q
2. Open large Python file (e.g. turtle.py in Python)
3. Near the top of the buffer, enter open paren and some characters.

The above commit extends the region to be font-locked using
`python-nav-end-of-statement'.  However, if there are unbalanced
parens, it may move point to the end of the buffer.  This causes
almost the entire buffer to be font-locked, which is not acceptable
for large files.

Attached is a patch to revert the commit in emacs-29 branch.

Best Regards,

--
In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo
 version 1.16.0, Xaw scroll bars) of 2023-05-27 built on ubuntu
Repository revision: 1eb5faa26113afe5895955a74594e3d7cf6ffe98
Repository branch: master
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