That is correct. ```setUp``` is called prior to each test method being called, whereas ```setUpClass``` is only called once before the collection of tests in a class are run. Similarly for ```tearDown``` and ```tearDownClass``` but we rarely use these. See https://github.com/SciTools/iris/blob/master/lib/iris/tests/__init__.py#L139-142 and https://github.com/SciTools/iris/blob/master/lib/iris/tests/__init__.py#L435-438 for examples. Note that there are also ```setUpModule``` and ```tearDownModule``` but we haven't used these.