but as for the prior issuethis probably shouldn' trigger new error on windows in for scripts that worked there formerly most programmers wouldn' expect unix comment lines to matter on windowsand wouldn' expect to be used by default just after installing book examples impact and fix in terms of my book examples portthis default caused multiple script failures after installing for both scripts with no #lineas well as scripts with unixcompatible #!/usr/bin/python line to fix just the latterchange all scripts in this category to name python explicitly instead of just python to fix both the former and the latter in single stepset the windows launcher' default to be globally with either py ini configuration file (see the launcher' documentation for detailsor py_python environment variable setting as shown in the earlier examples ( set py_python= as mentioned in the prior pointmanually changing your file associations is another solutionbut none of these options seem simpler than those imposed by prior install schemes pitfall the new path extension option besides installing the new launcherthe windows python installer can automatically add the directory containing ' python exe executable to your system path setting the reasoning behind this is that it might make life easier for some windows beginners--they can type just python instead of the full directory path to it this isn' feature of the launcher per seand shouldn' cause scripts to fail in general it had no impact on the book examples but it seems to clash with the launcher' operation and goalsand may be best avoided this is bit subtlebut 'll explain why as describedthe new launcher' py and pyw executables are by default installed on your system search pathand running them requires neither directory paths nor path settings if you start scripts with py instead of python command linesthe new path feature is irrelevant in factpy completely subsumes python in most contexts given that file associations will launch py or pyw instead of python anyhowyou probably should too --using python instead of py may prove redundant and inconsistentand might even launch version different than that used in launcher contexts should the two schemessettings grow out of sync in shortadding python to path seems contradictory to the new launcher' worldviewand potentially error-prone also note that updating your path assumes you want python command to run normallyand this feature is disabled by defaultbe sure to select this in the install screen if you want this to work (but not if you don' !due to the second pitfall mentioned earliermany users may still need to set py_python to for programs run by icon clicks that invoke the new launcherwhich seems no simpler than setting patha step that the pitfalls of the new windows launcher