class TestMain_Sample_File1(Test_With_File):

    def test_should_produce_known_output(self):
        with open('temp', 'w') as target:
            the_function_that_does_real_work('config1.txt', arg2=100, arg3=
                15, out=target)
self.assertFileMatches('output/config1.100.15.201202011733', 'temp')
regression testing the entire app in Python