#22 integrating benchmarks

tox.ini

@@ -32,10 +32,9 @@ commands =
 basepython = python
 setenv =
     PYTHONPATH = {toxinidir}
-whitelist_externals = ls
-                      xargs
+whitelist_externals = sh
 commands =
-    ls benchmarks/*.py  | xargs -n 1 python
+    sh -c 'ls benchmarks/*.py  | xargs -n 1 python'
 
 [testenv]
 whitelist_externals = xvfb-run