[ussuri][goal] Cleanup python 2.7 removal

OpenStack is dropping the py2.7 support in ussuri cycle.

Complete discussion & schedule can be found in
- http://lists.openstack.org/pipermail/openstack-discuss/2019-October/010142.html
- https://etherpad.openstack.org/p/drop-python2-support

Ussuri Communtiy-wide goal:
https://governance.openstack.org/tc/goals/selected/ussuri/drop-py27.html

This removes some cruft from Python 2.7 support.
Raise requests lower-constraint to satisfy oslo.config.

Change-Id: I47cc8ab5b348af28062ab3ff5329b96d2cbccdbb

doc/requirements.txt

@@ -1,4 +1,4 @@
-sphinx>=1.8.0,!=2.1.0;python_version>='3.4' # BSD
+sphinx>=1.8.0,!=2.1.0 # BSD
 sphinxcontrib-httpdomain>=1.3.0 # BSD
 sphinxcontrib-pecanwsme>=0.8.0 # Apache-2.0
 openstackdocstheme>=1.30.0 # Apache-2.0

lower-constraints.txt

@@ -41,7 +41,7 @@ python-subunit==1.0.0
 pytz==2013.6
 PyYAML==3.12
 reno==2.5.0
-requests==2.14.2
+requests==2.18.0
 requestsexceptions==1.2.0
 six==1.10.0
 snowballstemmer==1.2.1

setup.cfg

@@ -6,6 +6,7 @@ description-file =
 author = OpenStack
 author-email = openstack-discuss@lists.openstack.org
 home-page = https://docs.openstack.org/mistral/latest/
+python-requires = >=3.6
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
@@ -13,8 +14,6 @@ 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 :: 3.6
     Programming Language :: Python :: 3.7
@@ -23,15 +22,6 @@ classifier =
 packages =
     mistral_lib
 
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-warning-is-error = 1
-
-[upload_sphinx]
-upload-dir = doc/build/html
-
 [compile_catalog]
 directory = mistral-lib/locale
 domain = mistral-lib
@@ -46,7 +36,3 @@ keywords = _ gettext ngettext l_ lazy_gettext
 mapping_file = babel.cfg
 output_file = mistral-lib/locale/mistral-lib.pot
 
-[build_releasenotes]
-all_files = 1
-build-dir = releasenotes/build
-source-dir = releasenotes/source

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>=2.0.0'],
     pbr=True)

tox.ini

@@ -7,7 +7,6 @@ ignore_basepython_conflict = True
 [testenv]
 basepython = python3
 usedevelop = True
-install_command = pip install {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
          PYTHONDONTWRITEBYTECODE = 1
          PYTHONWARNINGS=default::DeprecationWarning