the nice part of this product is that you actually create python code to perform the testing your script is simply anotherspecializedapplication that tests the main application for problems you may be thinking that the scriptsrather than your professionally written applicationcould be bug ridden the testing script is designed to be extremely simplewhich will keep scripting errors small and quite noticeable of courseerrors can (and sometimes dohappenso yeswhen you can' find problem with your applicationyou do need to check the script tidying your code using isort it may seem like an incredibly small thingbut code can get messyespecially if you don' place all your import statements at the top of the file in alphabetical order in some situationsit becomes difficultif not impossibleto figure out what' going on with your code when it isn' kept neat the isort utility (seemingly small task of sorting your import statements and ensuring that they all appear at the top of the source code file this small step can have significant effect on your ability to understand and modify the source code just knowing which modules particular module needs can be help in locating potential problems for exampleif you somehow get an older version of needed module on your systemknowing which modules the application needs can make the process of finding that module easier in additionknowing which modules an application needs is important when it comes time to distribute your application to users knowing that the user has the correct modules available helps ensure that the application will run as anticipated providing version control using mercurial the applications you created while working through this book aren' very complex in factafter you finish this book and move on to more advanced training applicationsyou're unlikely to need version control howeverafter you start working in an organizational development environment in which you create real applications that users need to have available at all timesversion control becomes essential version control is simply the act of keeping