diff --git a/doc/source/conf.py b/doc/source/conf.py
index f4277c9..b412421 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -62,9 +62,6 @@ pygments_style = 'sphinx'
 # html_static_path = ['static']
 html_theme = 'openstackdocs'
 
-# Must set this variable to include year, month, day, hours, and minutes.
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
-
 # Output file base name for HTML help builder.
 htmlhelp_basename = '%sdoc' % project
 
diff --git a/setup.cfg b/setup.cfg
index 064da7f..bda0a37 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -6,6 +6,7 @@ description-file =
 author = OpenStack
 author-email = openstack-discuss@lists.openstack.org
 home-page = https://docs.openstack.org/contributors/
+python-requires = >=3.6
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
@@ -13,13 +14,8 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.5
-
-[build_sphinx]
-all-files = 1
-warning-is-error = 1
-source-dir = doc/source
-build-dir = doc/build
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3 :: Only
diff --git a/setup.py b/setup.py
index 056c16c..f63cc23 100644
--- a/setup.py
+++ b/setup.py
@@ -16,14 +16,6 @@
 # THIS FILE IS MANAGED BY THE GLOBAL REQUIREMENTS REPO - DO NOT EDIT
 import setuptools
 
-# In python < 2.7.4, a lazy loading of package `pbr` will break
-# setuptools if some other modules registered functions in `atexit`.
-# solution from: http://bugs.python.org/issue15881#msg170215
-try:
-    import multiprocessing  # noqa
-except ImportError:
-    pass
-
 setuptools.setup(
-    setup_requires=['pbr'],
+    setup_requires=['pbr>=2.0.0'],
     pbr=True)
diff --git a/test-requirements.txt b/test-requirements.txt
index bd3340b..d977e73 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -2,7 +2,6 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7'  # BSD
-sphinx!=1.6.6,!=1.6.7,>=1.6.2;python_version>='3.4'  # BSD
+sphinx!=1.6.6,!=1.6.7,>=1.6.2  # BSD
 openstackdocstheme>=1.28.0  # Apache-2.0
 doc8>=0.6.0  # Apache-2.0
diff --git a/tox.ini b/tox.ini
index 6f35361..b5786bd 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,7 @@
 [tox]
-minversion = 2.0
+minversion = 3.1.0
 envlist = docs,pep8
+ignore_basepython_conflict = True
 skipsdist = True
 
 [testenv]