run examples from python instead of shell

tox.ini

@@ -97,8 +97,7 @@ commands =
 ; run examples from subfolder to ensure that resources are accessed via resources and not via relative paths
     sh -c 'mkdir -p {envtmpdir}/c236d3c240d61a0969d4cb59e2180ce5'
 ; pipe echo into python since some examples expect input to close the window after the example is run
-;    sh -c 'cd {envtmpdir}/c236d3c240d61a0969d4cb59e2180ce5 &&  python {toxinidir}/benchmarks/run_all_examples.py'
-    sh -c 'python {toxinidir}/benchmarks/run_all_examples.py'
+    sh -c 'cd {envtmpdir}/c236d3c240d61a0969d4cb59e2180ce5 &&  python {toxinidir}/benchmarks/run_all_examples.py'
 
 [testenv:notebooks]
 basepython = python