diff -Naur a/tests/test_ansi2html.py b/tests/test_ansi2html.py
--- a/tests/test_ansi2html.py	2022-01-31 02:47:37.000000000 -0600
+++ b/tests/test_ansi2html.py	2022-07-04 10:52:52.501422154 -0500
@@ -27,7 +27,7 @@
 from subprocess import run
 from typing import List
 
-from mock import patch
+from unittest.mock import patch
 
 from ansi2html import Ansi2HTMLConverter
 from ansi2html.converter import (
diff -Naur a/tox.ini b/tox.ini
--- a/tox.ini	2022-01-31 02:47:37.000000000 -0600
+++ b/tox.ini	2022-07-04 10:53:05.854315113 -0500
@@ -13,7 +13,6 @@
     # PYTHONWARNINGS=error
     COVERAGE_FILE = {env:COVERAGE_FILE:{toxworkdir}/.coverage.{envname}}
 deps =
-    mock
     pytest
     pytest-cov
 sitepackages = False