Replace existing run_tests.py script with a pytest script The existing run_test.py script is quite old, a bit restrictive, and doesn't always behave as documented. The pytest testing tool is mature, well documented, and maintained. The run_tests.py script is generating by installing py.test and running: py.tests --genscript=run_tests.py Note: to generate a script that is compatible with python2.6 the command needs to be run using python2.6