update Python build matrix

.github/workflows/python-ci-tests.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.5, 3.6, 3.7, 3.8]
+        python-version: [3.6, 3.7, 3.8, 3.9]
 
     name: Python ${{ matrix.python-version }} Build
     steps:

setup.py

@@ -40,10 +40,10 @@ setup(
         'Topic :: Security',
         'License :: OSI Approved :: BSD License',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
     ],
     keywords='stix stix2 json cti cyber threat intelligence',
     packages=find_packages(exclude=['*.test', '*.test.*']),

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py35,py36,py37,py38,packaging,pre-commit-check
+envlist = py36,py37,py38,py39,packaging,pre-commit-check
 
 [testenv]
 deps =
@@ -32,7 +32,7 @@ commands =
 
 [gh-actions]
 python =
-  3.5: py35
   3.6: py36
   3.7: py37
   3.8: py38, packaging, pre-commit-check
+  3.9: py39, packaging, pre-commit-check