Fix Python 3.9 setup in Travis CI

oxan · oxan · commit 1c620272290c · 2020-04-17T12:38:15.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,9 +1,11 @@
-language: python
+os: linux
+dist: bionic
 
+language: python
 python:
   - "3.7"
   - "3.8"
-  - "3.9"
+  - "3.9-dev"
 
 install: pip install tox-travis codecov
 script: tox
