updated travis to python3.9

Laurent PINSON · Laurent PINSON · commit eb59a989145f · 2022-05-24T11:35:39.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,6 +1,6 @@
 language: python
 python:
-  - "3.7"
+  - "3.9"
 install: "pip install -r requirements.txt"
 script: make clean coverage docs dist
 deploy:
