Try to fix Travis CI

diff --git a/.travis.yml b/.travis.yml
index ab5b6d447896028f3e176c41ab67cdbec693a41e..eb204dbfbb6fd69d9f649735972917ca397edaa9 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,6 +21,7 @@ install:
 
 # command to run tests
 before_script:
+- pip install coverage -U
 - pip install coveralls
 
 script: