Use Python 3.7+ in testing.

diff --git a/.travis.yml b/.travis.yml
index 03f3e8115c6020f138e75c0a642225746bba1965..ebaca860325d695cc2a83f1abd98626e8a2f2ffe 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,9 @@
 language: python
 
 python:
-  - "2.7"
+  - "3.7"
+  - "3.8"
+  - "3.9"
 
 install:
   - pip install flake8