diff --git a/python-pyserial.changes b/python-pyserial.changes
index d4e336f..ad74806 100644
--- a/python-pyserial.changes
+++ b/python-pyserial.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Mon Jul 29 15:07:43 UTC 2024 - John Paul Adrian Glaubitz <adrian.glaubitz@suse.com>
+
+- Cherry-pick upstream patch to fix tests with Python 3.13
+  * replace-deprecated-unittest-function.patch
+
 -------------------------------------------------------------------
 Sun Apr 23 23:19:35 UTC 2023 - Matej Cepl <mcepl@suse.com>
 
diff --git a/python-pyserial.spec b/python-pyserial.spec
index a10f031..6674fbe 100644
--- a/python-pyserial.spec
+++ b/python-pyserial.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package python-pyserial
 #
-# Copyright (c) 2023 SUSE LLC
+# Copyright (c) 2024 SUSE LLC
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -25,12 +25,14 @@ License:        Python-2.0
 Group:          Development/Languages/Python
 URL:            https://github.com/pyserial/pyserial
 Source:         https://files.pythonhosted.org/packages/source/p/pyserial/pyserial-%{version}.tar.gz
+# PATCH-FIX-UPSTREAM - pyserial/pyserial#757 - Replace deprecated unittest.findTestCases function
+Patch:          https://github.com/pyserial/pyserial/pull/757.patch#/replace-deprecated-unittest-function.patch
 BuildRequires:  %{python_module setuptools}
 BuildRequires:  fdupes
 BuildRequires:  python-rpm-macros
 BuildRequires:  python3-Sphinx
 Requires(post): update-alternatives
-Requires(preun):update-alternatives
+Requires(preun): update-alternatives
 Provides:       python-serial = %{version}
 Obsoletes:      python-serial < %{version}
 BuildArch:      noarch
@@ -52,6 +54,7 @@ Documentation, examples, and help files for %{name}.
 
 %prep
 %setup -q -n pyserial-%{version}
+%patch -P0 -p1
 
 # Unnecessary
 rm serial/tools/list_ports_windows.py \
diff --git a/replace-deprecated-unittest-function.patch b/replace-deprecated-unittest-function.patch
new file mode 100644
index 0000000..520f41b
--- /dev/null
+++ b/replace-deprecated-unittest-function.patch
@@ -0,0 +1,30 @@
+From 239f840076bf9da76906dc029f26a423fef4a698 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20Van=C4=9Bk?= <arkamar@atlas.cz>
+Date: Fri, 7 Jun 2024 16:45:15 +0200
+Subject: [PATCH] Replace deprecated unittest.findTestCases function
+
+The unittest.findTestCases function was deprecated in Python 3.11 and
+later removed in Python 3.13. The TestLoader methods should be used
+instead [1].
+
+[1] https://docs.python.org/3.13/whatsnew/3.13.html#unittest
+
+Fixes: https://github.com/pyserial/pyserial/issues/754
+---
+ test/run_all_tests.py | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/test/run_all_tests.py b/test/run_all_tests.py
+index e0797e7e..f09fe9bb 100644
+--- a/test/run_all_tests.py
++++ b/test/run_all_tests.py
+@@ -37,7 +37,8 @@
+         print("skipping {}".format(modulename))
+     else:
+         module.PORT = PORT
+-        testsuite = unittest.findTestCases(module)
++        loader = unittest.TestLoader()
++        testsuite = loader.loadTestsFromModule(module)
+         print("found {} tests in {!r}".format(testsuite.countTestCases(), modulename))
+         mainsuite.addTest(testsuite)
+