diff --git a/tox.ini b/tox.ini
index 88fccdc014..c502b15b7f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -59,7 +59,6 @@ commands = python setup.py build_sphinx
 downloadcache = ~/cache/pip
 
 [flake8]
-builtins = _
 exclude = .venv,.git,.tox,dist,*openstack/common*,*lib/python*,*egg,build,panel_template,dash_template,local_settings.py,*/local/*,*/test/test_plugins/*
 # E127 continuation line over-indented for visual indent
 # E128 continuation line under-indented for visual indent