def test_commandline_explicit_interp(tmpdir):
 subprocess.check_call([sys.executable, VIRTUALENV_SCRIPT, '-p', sys.executable, str(tmpdir.join('venv'))])

def test_commandline_explicit_interp ( tmpdir ) : subprocess . check_call ( [ sys . executable , VIRTUALENV_SCRIPT , '-p' , sys . executable , str ( tmpdir . join ( 'venv' ) ) ] )
specifying the python interpreter should work .