import tools from other module files one of the modules is designated as the main or top-level fileor "script"--the file launched to start the entire programwhich runs line by line as usual below this levelit' all modules importing modules we'll delve into such architectural issues in more detail later in this book this is mostly interested in the fact that import operations run the code in file that is being loaded as final step because of thisimporting file is yet another way to launch it for instanceif you start an interactive session (from system command line or otherwise)you can run the script py file you created earlier with simple import (be sure to delete the input line you added in the prior section firstor you'll need to press enter for no reason) :\codec:\python \python import script win spam!spam!spam!spam!spam!spam!spam!spamthis worksbut only once per session (reallyprocess-- program runby default after the first importlater imports do nothingeven if you change and save the module' source file again in another windowchange script py in text edit window to print * import script import script this is by designimports are too expensive an operation to repeat more than once per fileper program run as you'll learn in imports must find filescompile them to byte codeand run the code if you really want to force python to run the file again in the same session without stopping and restarting the sessionyou need to instead call the reload function available in the imp standard library module (this function is also simple built-in in python xbut not in )from imp import reload must load from module in (onlyreload(script win spam!spam!spam!spam!spam!spam!spam!spamthe from statement here simply copies name out of module (more on this soonthe reload function itself loads and runs the current version of your file' codepicking up changes if you've modified and saved it in another window module imports and reloads