Sorry, the script didn't create the diff properly. Here's the real debdiff.
diff -Nru stdeb-0.10.0/debian/changelog stdeb-0.10.0/debian/changelog
--- stdeb-0.10.0/debian/changelog 2022-05-25 15:53:36.000000000 -0400
+++ stdeb-0.10.0/debian/changelog 2024-08-08 23:12:17.000000000 -0400
@@ -1,3 +1,11 @@
+stdeb (0.10.0-2.1) unstable; urgency=medium
+
+ * Non-maintainer upload.
+ * Cherry-pick upstream patch for fixing configparser usage
+ for Python 3.12+ (Closes: #1074723)
+
+ -- Kunal Mehta <lego...@debian.org> Thu, 08 Aug 2024 23:12:17 -0400
+
stdeb (0.10.0-2) unstable; urgency=medium
* Bump debhelper from old 12 to 13.
diff -Nru stdeb-0.10.0/debian/patches/0005-Migrate-off-SafeConfigParser.patch stdeb-0.10.0/debian/patches/0005-Migrate-off-SafeConfigParser.patch
--- stdeb-0.10.0/debian/patches/0005-Migrate-off-SafeConfigParser.patch 1969-12-31 19:00:00.000000000 -0500
+++ stdeb-0.10.0/debian/patches/0005-Migrate-off-SafeConfigParser.patch 2024-08-08 23:03:05.000000000 -0400
@@ -0,0 +1,64 @@
+From: Luca Della Vedova <luc...@intrinsic.ai>
+Date: Tue, 18 Jun 2024 16:54:16 +0800
+Subject: Migrate off SafeConfigParser
+Origin: https://github.com/astraw/stdeb/pull/196
+Signed-off-by: Luca Della Vedova <luc...@intrinsic.ai>
+---
+ stdeb/cli_runner.py | 7 +------
+ stdeb/util.py | 11 +++--------
+ 2 files changed, 4 insertions(+), 14 deletions(-)
+
+diff --git a/stdeb/cli_runner.py b/stdeb/cli_runner.py
+index e4cb6f9..0d32329 100644
+--- a/stdeb/cli_runner.py
++++ b/stdeb/cli_runner.py
+@@ -3,12 +3,7 @@ import os
+ import shutil
+ import subprocess
+ import sys
+-try:
+- # python 2.x
+- from ConfigParser import SafeConfigParser # noqa: F401
+-except ImportError:
+- # python 3.x
+- from configparser import SafeConfigParser # noqa: F401
++from configparser import ConfigParser # noqa: F401
+ from distutils.util import strtobool
+ from distutils.fancy_getopt import FancyGetopt, translate_longopt
+ from stdeb.util import stdeb_cmdline_opts, stdeb_cmd_bool_opts
+diff --git a/stdeb/util.py b/stdeb/util.py
+index dc97faf..fb39c53 100644
+--- a/stdeb/util.py
++++ b/stdeb/util.py
+@@ -9,12 +9,7 @@ import shutil
+ import sys
+ import time
+ import codecs
+-try:
+- # Python 2.x
+- import ConfigParser
+-except ImportError:
+- # Python 3.x
+- import configparser as ConfigParser
++import configparser as ConfigParser
+ import subprocess
+ import tempfile
+ import stdeb # noqa: F401
+@@ -730,7 +725,7 @@ def check_cfg_files(cfg_files, module_name):
+ example.
+ """
+
+- cfg = ConfigParser.SafeConfigParser()
++ cfg = ConfigParser.ConfigParser()
+ cfg.read(cfg_files)
+ if cfg.has_section(module_name):
+ section_items = cfg.items(module_name)
+@@ -801,7 +796,7 @@ class DebianInfo:
+ if len(cfg_files):
+ check_cfg_files(cfg_files, module_name)
+
+- cfg = ConfigParser.SafeConfigParser(cfg_defaults)
++ cfg = ConfigParser.ConfigParser(cfg_defaults)
+ for cfg_file in cfg_files:
+ with codecs.open(cfg_file, mode='r', encoding='utf-8') as fd:
+ cfg.readfp(fd)
diff -Nru stdeb-0.10.0/debian/patches/0006-readfp-read_file.patch stdeb-0.10.0/debian/patches/0006-readfp-read_file.patch
--- stdeb-0.10.0/debian/patches/0006-readfp-read_file.patch 1969-12-31 19:00:00.000000000 -0500
+++ stdeb-0.10.0/debian/patches/0006-readfp-read_file.patch 2024-08-08 23:03:14.000000000 -0400
@@ -0,0 +1,22 @@
+From: Luca Della Vedova <luc...@intrinsic.ai>
+Date: Tue, 18 Jun 2024 17:07:18 +0800
+Subject: readfp -> read_file
+Origin: https://github.com/astraw/stdeb/pull/196
+Signed-off-by: Luca Della Vedova <luc...@intrinsic.ai>
+---
+ stdeb/util.py | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/stdeb/util.py b/stdeb/util.py
+index fb39c53..cfab645 100644
+--- a/stdeb/util.py
++++ b/stdeb/util.py
+@@ -799,7 +799,7 @@ class DebianInfo:
+ cfg = ConfigParser.ConfigParser(cfg_defaults)
+ for cfg_file in cfg_files:
+ with codecs.open(cfg_file, mode='r', encoding='utf-8') as fd:
+- cfg.readfp(fd)
++ cfg.read_file(fd)
+
+ if sdist_dsc_command is not None:
+ # Allow distutils commands to override config files (this lets
diff -Nru stdeb-0.10.0/debian/patches/series stdeb-0.10.0/debian/patches/series
--- stdeb-0.10.0/debian/patches/series 2022-05-25 15:53:36.000000000 -0400
+++ stdeb-0.10.0/debian/patches/series 2024-08-08 22:22:35.000000000 -0400
@@ -2,3 +2,5 @@
bump_standards-version.patch
add_debian_watch.patch
python3.patch
+0005-Migrate-off-SafeConfigParser.patch
+0006-readfp-read_file.patch
