Using proper default now...
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 718306a..ef199ed 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -2,7 +2,8 @@
 
 ###
 # Script requirments:
-apt-get install -y python-yaml virtualenv git
+#apt-get install -y python-yaml virtualenv git
+which virtualenv &> /dev/null || apt-get install -y virtualenv
 
 set -e
 [ -n "$DEBUG" ] && set -x