diff --git a/tox.ini b/tox.ini
index 0277949..61d3e53 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,7 +2,6 @@
 minversion = 2.0
 envlist = py35,py36,py27,pep8
 skipsdist = True
-basepython = python3
 
 [testenv]
 usedevelop = True
@@ -14,6 +13,7 @@ setenv =
    OS_TEST_TIMEOUT=60
 deps = -r{toxinidir}/test-requirements.txt
 commands = stestr run {posargs}
+basepython = python3
 
 [testenv:pep8]
 commands = flake8 {posargs}