[Python] Why does Python regular expression give different result for the following 2...

While investigating the semantic difference between quantifiers based on length and count, I noticed that Python 3 regular expression gave different result for the following 2 regular expressions (notice the quantifiers + and *:

Python 3.10.16 (main, Dec 7 2024, 13:31:33) [Clang 16.0.0 (clang-1600.0.26.6)] on darwin
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>>> import re
>>> re.sub('(.{4,5})+', '-', '1234123412341234')
'-4'
>>> re.sub('(.{4,5})*', '-', '1234123412341234')
'--4-'
>>>


And I was able to reproduce this in PHP, presumably because they both use PCRE behind the back:

$ php -a
Interactive shell

php > echo preg_replace('/(.{4,5})+/', '-', '1234123412341234');
-4
php > echo preg_replace('/(.{4,5})*/', '-', '1234123412341234');
--4-
php >


How come?

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