My reasons for doing this were that we have 3 types of problems we are testing: schematic response, custom response that uses a `cfn` script, and custom response that uses an `answer` script.  Each uses its script to determine what the correct and incorrect answers are so it makes sense to keep each script close to the definition of the correct and incorrect responses.  I could put their definitions into the general setUp method, but it seems to me less clear having them all defined together in one place than having each defined in its own specific set_up method, since they are only relevant in the appropriate {script, correct, incorrect} sets.  Does this make sense?