diff --git a/tox.ini b/tox.ini
index b7e02e6..7bae776 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,9 +1,11 @@
 [tox]
-minversion = 2.0
-envlist = pep8,py36,py37,py27
+minversion = 3.1.1
+envlist = pep8,py36,py37
 skipsdist = True
+ignore_basepython_conflict = True
 
 [testenv]
+basepython = python3
 usedevelop = True
 install_command = pip install -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
 setenv =
@@ -21,7 +23,6 @@
     stestr --test-path ./patrole_tempest_plugin/tests/unit run {posargs}
 
 [testenv:pep8]
-basepython = python3
 deps =
     -r{toxinidir}/test-requirements.txt
 commands =
@@ -30,15 +31,12 @@
     check-uuid --package patrole_tempest_plugin.tests.api
 
 [testenv:uuidgen]
-basepython = python3
 commands = check-uuid --package patrole_tempest_plugin.tests.api --fix
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:cover]
-basepython = python3
 commands = rm -rf *.pyc
            rm -rf cover
            rm -f .coverage
@@ -54,7 +52,6 @@
                       rm
 
 [testenv:docs]
-basepython = python3
 deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
   -r{toxinidir}/requirements.txt
@@ -65,7 +62,6 @@
 whitelist_externals = rm
 
 [testenv:pdf-docs]
-basepython = python3
 deps = {[testenv:docs]deps}
 whitelist_externals =
    make
@@ -74,7 +70,6 @@
    make -C doc/build/pdf
 
 [testenv:releasenotes]
-basepython = python3
 deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
   -r{toxinidir}/requirements.txt
@@ -85,11 +80,9 @@
 whitelist_externals = rm
 
 [testenv:debug]
-basepython = python3
 commands = oslo_debug_helper -t patrole_tempest_plugin/tests {posargs}
 
 [testenv:genconfig]
-basepython = python3
 commands = oslo-config-generator --config-file etc/config-generator.patrole.conf
 
 [flake8]
@@ -114,7 +107,6 @@
 local-check-factory = patrole_tempest_plugin.hacking.checks.factory
 
 [testenv:lower-constraints]
-basepython = python3
 deps =
   -c{toxinidir}/lower-constraints.txt
   -r{toxinidir}/test-requirements.txt