diff --git a/tox.ini b/tox.ini
index 5cac8ebc..b8a91a6c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,18 +1,16 @@
 [tox]
 envlist = pypy,py39,pep8
-ignore_basepython_conflict = true
 minversion = 3.18.0
 
 [testenv]
-basepython = python3
-setenv = VIRTUAL_ENV={envdir}
 usedevelop = True
 deps =
-       -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
-       -r{toxinidir}/requirements.txt
-       -r{toxinidir}/test-requirements.txt
-commands = find . -type f -name "*.py[c|o]" -delete
-           stestr run --slowest {posargs}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -r{toxinidir}/requirements.txt
+  -r{toxinidir}/test-requirements.txt
+commands =
+  find . -type f -name "*.py[c|o]" -delete
+  stestr run --slowest {posargs}
 allowlist_externals = find
 
 [testenv:debug]
@@ -36,13 +34,13 @@ passenv = OS_*
 
 [testenv:cover]
 setenv =
-    PYTHON=coverage run --source heatclient --parallel-mode
+  PYTHON=coverage run --source heatclient --parallel-mode
 commands =
-    stestr run {posargs}
-    coverage combine
-    coverage html -d cover
-    coverage xml -o cover/coverage.xml
-    coverage report
+  stestr run {posargs}
+  coverage combine
+  coverage html -d cover
+  coverage xml -o cover/coverage.xml
+  coverage report
 
 [testenv:docs]
 deps =