or import bext to check if the installation worked if these import instruction don' produce an error messagethese modules installed correctly and you'll be able to run the projects in this book that use these modules copying the code from this book programming is skill that you improve by programming don' just read the code in this book or copy and paste it to your computer take the time to enter the code into the editor for yourself open new file in your code editor and enter the code pay attention to the line numbers in this book and your editor to make sure you aren' accidentally skipping any lines if you encounter errorsuse the online diff tool at bigbookpython/diffto show you any differences between your code and the code in this book to get better understanding of these programstry running them under the debugger after entering the source code and running it few timestry making experimental changes to the code the comments marked with (!have suggestions for small changes you can makeand each project lists suggestions for larger modifications nexttry re-creating the program from scratch without looking at the source code in this book it doesn' have to be exactly the same as this programyou can invent your own versiononce you've worked through the programs in this bookyou might want to start creating your own most modern video games and software applications are complicatedrequiring teams of programmersartistsand designers to create howevermany boardcardand paper-and-pencil games are often simple enough to re-create as program many of these fall under the category of "abstract strategy games you can find list of them at running programs from the terminal the programming projects in this book that use the bext module have colorful text for their output howeverthese colors won' appear when you run them from muidleor other editors these programs should be run from terminalalso called command linewindow on windowsrun the command prompt program from the start menu on macosrun terminal from spotlight on ubuntu linuxrun terminal from ubuntu dash or press ctrl-alt- when the terminal window appearsyou should change the current directory to the folder with your py files with the cd (change directorycommand (directory is another term for folder for exampleif were on windows and saved my python programs to the :\users\al folderi would enter the following line introduction xxi