Hi!

While rebuilding the python related packages against the Python 3.15rc2
version we found that nibabel fails to build from source [1].

The failure happens because test_DeterministicGzipFile and
test_DeterministicGzipFile_fileobj fail due to a discrepancy in the
default compression levels of gzip files, python 3.15 uses now
compresslevel=6

To fix this, I've made a patch to use None as the default compresslevel,
and let Python set it, instead of forcing it to 9.

I applied the fix in the sandbox [2] to be able to build the packages
that depend on nibabel, please consider applying the patch to support
the upcoming 3.15 version.

Setting the severity to important for now. Once Python 3.15 is released,
it will be added to python3-defaults and this bug will become release
critical.

Happy hacking,

[1]: https://debusine.debian.net/debian/r-python-python3.15/artifact/4478755/
[2]: https://debusine.debian.net/debian/r-python-python3.15/

Hello,

Bug #1146887 in pynifti reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/med-team/nibabel/-/commit/d55b7510739d51137914dabd6a39bd0e1528d950

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1146887

We believe that the bug you reported is fixed in the latest version of
nibabel, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1146887@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Andreas Tille <tille@debian.org> (supplier of updated nibabel package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Wed, 09 Sep 2026 13:44:37 +0200
Source: nibabel
Architecture: source
Version: 5.4.2-5
Distribution: unstable
Urgency: medium
Maintainer: Debian Med Packaging Team <debian-med-packaging@lists.alioth.debian.org>
Changed-By: Andreas Tille <tille@debian.org>
Closes: 1146887
Changes:
 nibabel (5.4.2-5) unstable; urgency=medium
 .
   * Team upload.
 .
   [ Maximiliano Curia ]
   * Fix test failures with Python 3.15
     Closes: #1146887
 .
   [ Andreas Tille ]
   * debhelper-compat = 14
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