Add Python 3.9 support

.github/workflows/pythonpackage.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.6, 3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2

CHANGES.rst

@@ -17,7 +17,8 @@ Added
 * IPv6 support in nft method.
 * Intercept DNS requests sent by systemd-resolved.
 * Set default tmark.
-* Fix python2 server compatibility
+* Fix python2 server compatibility.
+* Python 3.9 support.
 
 Fixed
 ~~~~~

setup.py

@@ -52,6 +52,7 @@ setup(
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
         "Topic :: System :: Networking",
     ],
     scripts=['bin/sudoers-add'],

tox.ini

@@ -5,12 +5,14 @@ envlist =
     py36,
     py37,
     py38,
+    py39,
 
 [testenv]
 basepython =
     py36: python3.6
     py37: python3.7
     py38: python3.8
+    py39: python3.9
 commands =
     pip install -e .
     # actual flake8 test