diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 7ec5232..befd853 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -19,10 +19,10 @@ jobs:
         with:
           ref: ${{ github.ref }}
 
-      - name: Set up Python 3.12
+      - name: Set up Python 3.13
         uses: actions/setup-python@v5
         with:
-          python-version: 3.12
+          python-version: 3.13
           allow-prereleases: true
       - name: Install dependencies
         run: |
@@ -39,7 +39,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [ "3.9", "3.10", "3.11", "3.12" ]
+        python-version: [ "3.10", "3.11", "3.12", "3.13" ]
 
     steps:
       - uses: actions/checkout@v4
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index b8c2f2b..57ba54a 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -9,7 +9,7 @@ version: 2
 build:
   os: ubuntu-22.04
   tools:
-    python: "3.11"
+    python: "3.13"
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
diff --git a/bin/jsonpointer b/bin/jsonpointer
index ba2117c..d3d27ae 100755
--- a/bin/jsonpointer
+++ b/bin/jsonpointer
@@ -1,5 +1,4 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
+#!/usr/bin/env python3
 
 
 import argparse
diff --git a/doc/conf.py b/doc/conf.py
index ed2a7f3..f472f57 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 #
 # python-json-pointer documentation build configuration file, created by
 # sphinx-quickstart on Sat Apr 13 16:52:59 2013.
@@ -11,7 +10,8 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
-import sys, os
+import os
+import sys
 
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
@@ -42,7 +42,7 @@
 master_doc = 'index'
 
 # General information about the project.
-project = u'python-json-pointer'
+project = 'python-json-pointer'
 copyright = jsonpointer.__author__
 
 # The version info for the project you're documenting, acts as replacement for
@@ -186,8 +186,8 @@
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title, author, documentclass [howto/manual]).
 latex_documents = [
-  ('index', 'python-json-pointer.tex', u'python-json-pointer Documentation',
-   u'Stefan Kögl', 'manual'),
+  ('index', 'python-json-pointer.tex', 'python-json-pointer Documentation',
+   'Stefan Kögl', 'manual'),
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
@@ -216,8 +216,8 @@
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    ('index', 'python-json-pointer', u'python-json-pointer Documentation',
-     [u'Stefan Kögl'], 1)
+  ('index', 'python-json-pointer', 'python-json-pointer Documentation',
+   ['Stefan Kögl'], 1)
 ]
 
 # If true, show URL addresses after external links.
@@ -230,8 +230,8 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-  ('index', 'python-json-pointer', u'python-json-pointer Documentation',
-   u'Stefan Kögl', 'python-json-pointer', 'One line description of project.',
+  ('index', 'python-json-pointer', 'python-json-pointer Documentation',
+   'Stefan Kögl', 'python-json-pointer', 'One line description of project.',
    'Miscellaneous'),
 ]
 
diff --git a/doc/index.rst b/doc/index.rst
index 7d079e8..e1e0aae 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -7,7 +7,7 @@ python-json-pointer
 ===================
 
 *python-json-pointer* is a Python library for resolving JSON pointers (`RFC
-6901 <http://tools.ietf.org/html/rfc6901>`_). Python 3.9+
+6901 <http://tools.ietf.org/html/rfc6901>`_). Python 3.10+
 and PyPy are supported.
 
 **Contents**
diff --git a/jsonpointer.py b/jsonpointer.py
index 3e97add..d64d729 100644
--- a/jsonpointer.py
+++ b/jsonpointer.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-#
 # python-json-pointer - An implementation of the JSON Pointer syntax
 # https://github.com/stefankoegl/python-json-pointer
 #
@@ -136,7 +134,7 @@ class JsonPointerException(Exception):
     pass
 
 
-class EndOfList(object):
+class EndOfList:
     """Result of accessing element "-" of a list"""
 
     def __init__(self, list_):
@@ -147,7 +145,7 @@ def __repr__(self):
                                      lst=repr(self.list_))
 
 
-class JsonPointer(object):
+class JsonPointer:
     """A JSON Pointer that can reference parts of a JSON document"""
 
     # Array indices must not contain:
@@ -294,7 +292,7 @@ def join(self, suffix):
         except:  # noqa E722
             raise JsonPointerException("Invalid suffix")
 
-    def __truediv__(self, suffix):  # Python 3
+    def __truediv__(self, suffix):
         return self.join(suffix)
 
     @property
diff --git a/makefile b/makefile
index c40b485..024d988 100644
--- a/makefile
+++ b/makefile
@@ -6,11 +6,11 @@ help:
 	@echo " - coverage: run tests with coverage"
 	@echo
 	@echo "To install jsonpointer, type"
-	@echo "  python setup.py install"
+	@echo "  python3 setup.py install"
 	@echo
 
 test:
-	python -munittest
+	python3 -munittest
 
 coverage:
 	coverage run --source=jsonpointer tests.py
diff --git a/setup.cfg b/setup.cfg
index ab8f354..4b36d81 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,3 @@
-[bdist_wheel]
-universal = 1
-
 [flake8]
 max-line-length = 120
 exclude = .git,.tox,dist,doc,*egg,build,.venv
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 75f5426..f353ac1 100644
--- a/setup.py
+++ b/setup.py
@@ -38,27 +38,28 @@
     'Operating System :: OS Independent',
     'Programming Language :: Python',
     'Programming Language :: Python :: 3',
-    'Programming Language :: Python :: 3.9',
     'Programming Language :: Python :: 3.10',
     'Programming Language :: Python :: 3.11',
     'Programming Language :: Python :: 3.12',
+    'Programming Language :: Python :: 3.13',
     'Programming Language :: Python :: Implementation :: CPython',
     'Programming Language :: Python :: Implementation :: PyPy',
     'Topic :: Software Development :: Libraries',
     'Topic :: Utilities',
 ]
 
-setup(name=PACKAGE,
-      version=VERSION,
-      description=DESCRIPTION,
-      long_description=long_description,
-      long_description_content_type="text/markdown",
-      author=AUTHOR,
-      author_email=EMAIL,
-      license=LICENSE,
-      url=WEBSITE,
-      py_modules=MODULES,
-      scripts=['bin/jsonpointer'],
-      classifiers=CLASSIFIERS,
-      python_requires='>=3.9',
-      )
+setup(
+    name=PACKAGE,
+    version=VERSION,
+    description=DESCRIPTION,
+    long_description=long_description,
+    long_description_content_type="text/markdown",
+    author=AUTHOR,
+    author_email=EMAIL,
+    license=LICENSE,
+    url=WEBSITE,
+    py_modules=MODULES,
+    scripts=['bin/jsonpointer'],
+    classifiers=CLASSIFIERS,
+    python_requires='>=3.10',
+)
diff --git a/tests.py b/tests.py
index 668982d..d7cee1f 100755
--- a/tests.py
+++ b/tests.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 
 import copy
 import doctest
@@ -370,7 +369,7 @@ def test_mock_dict_sanity(self):
             '/root/1/2': '3',
         }
 
-        for path, expected_value in iter(path_to_expected_value.items()):
+        for path, expected_value in path_to_expected_value.items():
             self.assertEqual(resolve_pointer(doc, path, default), expected_value)
 
     def test_mock_dict_returns_default(self):
@@ -382,7 +381,7 @@ def test_mock_dict_returns_default(self):
             '/x/y/z/d': default
         }
 
-        for path, expected_value in iter(path_to_expected_value.items()):
+        for path, expected_value in path_to_expected_value.items():
             self.assertEqual(resolve_pointer(doc, path, default), expected_value)
 
     def test_mock_dict_raises_key_error(self):