diff --git a/tox.ini b/tox.ini
index 21696eb..4431289 100644
--- a/tox.ini
+++ b/tox.ini
@@ -23,11 +23,12 @@
 passenv = OS_STDOUT_CAPTURE OS_STDERR_CAPTURE OS_TEST_TIMEOUT OS_TEST_LOCK_PATH TEMPEST_CONFIG TEMPEST_CONFIG_DIR http_proxy HTTP_PROXY https_proxy HTTPS_PROXY no_proxy NO_PROXY ZUUL_CACHE_DIR REQUIREMENTS_PIP_LOCATION GENERATE_TEMPEST_PLUGIN_LIST
 usedevelop = True
 install_command =
-    {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
+    {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=83b1de74834fbcdbe749e270c29e76cdc28f85d5} {opts} {packages}
 whitelist_externals = *
 deps =
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/test-requirements.txt
+    pycodestyle<=2.3.1
 commands =
     find . -type f -name "*.pyc" -delete
     stestr --test-path ./tempest/tests run {posargs}