diff --git a/heat_dashboard/content/stacks/forms.py b/heat_dashboard/content/stacks/forms.py
index e6e2a701..15b91dc3 100644
--- a/heat_dashboard/content/stacks/forms.py
+++ b/heat_dashboard/content/stacks/forms.py
@@ -426,7 +426,7 @@ class CreateStackForm(forms.SelfHandlingForm):
         fields = {
             'stack_name': data.get('stack_name'),
             'timeout_mins': data.get('timeout_mins'),
-            'disable_rollback': not(data.get('enable_rollback')),
+            'disable_rollback': not data.get('enable_rollback'),
             'parameters': dict(params_list),
             'files': json.loads(data.get('parameters')).get('files'),
             'template': json.loads(data.get('parameters')).get('template')
@@ -482,7 +482,7 @@ class EditStackForm(CreateStackForm):
         fields = {
             'stack_name': data.get('stack_name'),
             'timeout_mins': data.get('timeout_mins'),
-            'disable_rollback': not(data.get('enable_rollback')),
+            'disable_rollback': not data.get('enable_rollback'),
             'parameters': dict(params_list),
             'files': json.loads(data.get('parameters')).get('files'),
             'template': json.loads(data.get('parameters')).get('template')
@@ -517,7 +517,7 @@ class PreviewStackForm(CreateStackForm):
         fields = {
             'stack_name': data.get('stack_name'),
             'timeout_mins': data.get('timeout_mins'),
-            'disable_rollback': not(data.get('enable_rollback')),
+            'disable_rollback': not data.get('enable_rollback'),
             'parameters': dict(params_list),
             'files': json.loads(data.get('parameters')).get('files'),
             'template': json.loads(data.get('parameters')).get('template')
diff --git a/requirements.txt b/requirements.txt
index a1f49477..9ef74432 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,8 +1,3 @@
-# Requirements lower bounds listed here are our best effort to keep them up to
-# date but we do not test them so no guarantee of having them all correct. If
-# you find any incorrect lower bounds, let us know or propose a fix.
-#
-# PBR should always appear first
 pbr>=5.5.0 # Apache-2.0
 python-heatclient>=1.10.0 # Apache-2.0
 
diff --git a/test-requirements.txt b/test-requirements.txt
index cc9df555..13b903e2 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,16 +1,7 @@
-# The order of packages is significant, because pip processes them in the order
-# of appearance. Changing the order has an impact on the overall integration
-# process, which may cause wedges in the gate later.
-# Order matters to the pip dependency resolver, so sorting this file
-# changes how packages are installed.  New dependencies should be
-# added in alphabetical order, however, some dependencies may need to
-# be installed in a specific order.
-#
-# Hacking should appear first in case something else depends on pep8
-hacking>=3.0.1,<3.1.0 # Apache-2.0
-#
+hacking>=6.1.0,<6.2.0 # Apache-2.0
+
 coverage!=4.4,>=4.0 # Apache-2.0
-flake8-import-order==0.12 # LGPLv3
+flake8-import-order>=0.18.0,<0.19.0 # LGPLv3
 nodeenv>=0.9.4 # BSD
 testtools>=2.2.0 # MIT
 
diff --git a/tox.ini b/tox.ini
index bc4f0e2a..5bbc1147 100644
--- a/tox.ini
+++ b/tox.ini
@@ -70,7 +70,8 @@ exclude = .venv,.git,.tox,dist,*lib/python*,*egg,build,panel_template,dash_templ
 # W504 line break after binary operator
 # (W503 and W504 are incompatible and we need to choose one of them.
 #  Existing codes follows W503, so we disable W504.)
-ignore = F405,W504
+# I202 Additional newline in a group of imports.
+ignore = F405,W504,I202
 max-complexity = 20
 import-order-style = pep8