diff --git a/os_api_ref/tests/base.py b/os_api_ref/tests/base.py
index 6e5e0dc..cd2bcdb 100644
--- a/os_api_ref/tests/base.py
+++ b/os_api_ref/tests/base.py
@@ -14,12 +14,13 @@
 # under the License.
 
 import os
+import pathlib
+import shutil
 
 import fixtures
 import tempfile
 import testtools
 
-from sphinx.testing.path import path
 from sphinx.testing.util import SphinxTestApp
 
 
@@ -32,16 +33,15 @@ _TRUE_VALUES = ('True', 'true', '1', 'yes')
 
 class with_app:
     def __init__(self, **kwargs):
-        if 'srcdir' in kwargs:
-            self.srcdir = path(kwargs['srcdir'])
+        self.srcdir = pathlib.Path(kwargs['srcdir'])
         self.sphinx_app_args = kwargs
 
     def __call__(self, f):
         def newf(*args, **kwargs):
             with tempfile.TemporaryDirectory() as tmpdirname:
-                tmpdir = path(tmpdirname)
-                tmproot = tmpdir / self.srcdir.basename()
-                self.srcdir.copytree(tmproot)
+                tmpdir = pathlib.Path(tmpdirname)
+                tmproot = tmpdir.joinpath(self.srcdir.name)
+                shutil.copytree(self.srcdir, tmproot)
                 self.sphinx_app_args['srcdir'] = tmproot
                 self.builddir = tmproot.joinpath('_build')
 
diff --git a/os_api_ref/tests/test_basic_example.py b/os_api_ref/tests/test_basic_example.py
index 83e2892..ba78658 100644
--- a/os_api_ref/tests/test_basic_example.py
+++ b/os_api_ref/tests/test_basic_example.py
@@ -74,12 +74,6 @@ class TestBasicExample(base.TestCase):
     def test_parameters(self):
         """Do we get some parameters table"""
         table = """<table class="docutils align-default">
-<colgroup>
-<col style="width: 20%"/>
-<col style="width: 10%"/>
-<col style="width: 10%"/>
-<col style="width: 60%"/>
-</colgroup>
 <thead>
 <tr class="row-odd"><th class="head"><p>Name</p></th>
 <th class="head"><p>In</p></th>
@@ -99,10 +93,6 @@ class TestBasicExample(base.TestCase):
 
     def test_rest_response(self):
         success_table = """<table class="docutils align-default">
-<colgroup>
-<col style="width: 30%"/>
-<col style="width: 70%"/>
-</colgroup>
 <thead>
 <tr class="row-odd"><th class="head"><p>Code</p></th>
 <th class="head"><p>Reason</p></th>
@@ -122,10 +112,6 @@ class TestBasicExample(base.TestCase):
 </table>"""
 
         error_table = """<table class="docutils align-default">
-<colgroup>
-<col style="width: 30%"/>
-<col style="width: 70%"/>
-</colgroup>
 <thead>
 <tr class="row-odd"><th class="head"><p>Code</p></th>
 <th class="head"><p>Reason</p></th>
diff --git a/os_api_ref/tests/test_microversions.py b/os_api_ref/tests/test_microversions.py
index 8281442..d6794a4 100644
--- a/os_api_ref/tests/test_microversions.py
+++ b/os_api_ref/tests/test_microversions.py
@@ -44,11 +44,11 @@ class TestMicroversions(base.TestCase):
     def test_rest_method(self):
         """Test that min / max mv css class attributes are set"""
         content = self.soup.find_all(class_='rp_min_ver_2_17')
-        self.assertRegexpMatches(
+        self.assertRegex(
             str(content[0]),
             '^<div class="operation-grp rp_min_ver_2_17 rp_max_ver_2_19 ?"')
         content = self.soup.find_all(class_='rp_max_ver_2_19')
-        self.assertRegexpMatches(
+        self.assertRegex(
             str(content[0]),
             '^<div class="operation-grp rp_min_ver_2_17 rp_max_ver_2_19 ?"')
 
@@ -56,12 +56,6 @@ class TestMicroversions(base.TestCase):
         """Test that min / max mv css class attributes are set in params"""
         table = """
 <table class="docutils align-default">
-<colgroup>
-<col style="width: 20%"/>
-<col style="width: 10%"/>
-<col style="width: 10%"/>
-<col style="width: 60%"/>
-</colgroup>
 <thead>
 <tr class="row-odd"><th class="head"><p>Name</p></th>
 <th class="head"><p>In</p></th>
diff --git a/os_api_ref/tests/test_warnings.py b/os_api_ref/tests/test_warnings.py
index 9fa9fef..a112986 100644
--- a/os_api_ref/tests/test_warnings.py
+++ b/os_api_ref/tests/test_warnings.py
@@ -17,6 +17,8 @@ test_os_api_ref
 Tests for `os_api_ref` module.
 """
 
+from collections import OrderedDict
+
 from bs4 import BeautifulSoup
 
 from os_api_ref.tests import base
@@ -55,11 +57,16 @@ class TestWarnings(base.TestCase):
 
     def test_missing_field(self):
         """Warning when missing type field in parameter file."""
+        # py312 changes string interpretation of OrderedDict.
+        # Prevent such failures by using OrderedDict directly
+        cmp_data = OrderedDict({
+            "description": "name_1 is missing type field.\n",
+            "in": "body",
+            "required": True
+        })
         self.assertIn(
             ("WARNING: Failure on key: name, values: " +
-             "OrderedDict([('description'," +
-             " 'name_1 is missing type field.\\n'), ('in', 'body')," +
-             " ('required', True)]). " +
+             f"{cmp_data}. " +
              "'NoneType' object has no attribute 'split'"),
             self.warning)
 
diff --git a/setup.cfg b/setup.cfg
index ceb213d..3deaefe 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -6,7 +6,7 @@ description_file =
 author = OpenStack
 author_email = openstack-discuss@lists.openstack.org
 home_page = https://docs.openstack.org/os-api-ref/latest/
-python_requires = >=3.8
+python_requires = >=3.9
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
@@ -15,8 +15,10 @@ classifier =
     Operating System :: POSIX :: Linux
     Programming Language :: Python
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
+    Programming Language :: Python :: 3.12
     Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: Implementation :: CPython
 
diff --git a/test-requirements.txt b/test-requirements.txt
index 0fd36ef..bf005dc 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -11,3 +11,6 @@ testtools>=2.2.0 # MIT
 beautifulsoup4>=4.6.0 # MIT
 stestr>=2.0.0 # Apache-2.0
 pre-commit>=2.6.0 # MIT
+
+# The minimum version requirement is specific to unit tests.
+sphinx>=7.2.0 # BSD