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Fixes hzdg#130

.github/workflows/ci.yml

@@ -0,0 +1,24 @@
+name: CI
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+jobs:
+  Build:
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        include:
+          - python-version: '3.6'
+          - python-version: '3.10'
+    steps:
+      - name: 'Set up Python ${{ matrix.python-version }}'
+        uses: actions/setup-python@v2
+        with:
+          python-version: '${{ matrix.python-version }}'
+      - uses: actions/checkout@v2
+      - run: pip install -U pip wheel setuptools tox tox-gh-actions
+      - run: tox

tox.ini

@@ -1,14 +1,24 @@
 [tox]
 envlist =
-    py{36,37,38,39}-django{22,30,31}
+    py{36,37,38}-django{22,30,31}
+    py{38,39,310}-django{40}
 
 [testenv]
 setenv = PYTHONPATH = {toxinidir}
 commands = py.test -s tests --cov=enumfields --cov-report=term-missing
 deps =
     djangorestframework>=3.7
     pytest-django
-    pytest-coverage
-    django22: Django>=2.2,<2.3
-    django30: Django>=3.0,<3.1
-    django31: Django>=3.1,<3.2
+    pytest-cov
+    django22: Django~=2.2.0
+    django30: Django~=3.0.0
+    django31: Django~=3.1.0
+    django40: Django~=4.0.0
+
+[gh-actions]
+python =
+    3.6 = py36
+    3.7 = py37
+    3.8 = py38
+    3.9 = py39
+    3.10 = py310