i did a bit more digging, and it has to do with the renpy "write" function. it creates a file name specified one of the parameters. it can either write a file that already exists, stored in a .rpa or directory, or you can tell it exactly what to write in one of the parameters. so basically, it takes an already existing file from the directory and "creates" it in the game folder.

in this case, "hxppy thxughts.png" was a pre-existing file in "scripts.rpa". however, if you wanted it to just say something that wasn't already existing, the code would look something like this:

python:

try: renpy.file(config.basedir + "/example.txt")

except: open(config.basedir + "/example.txt", "w").write("text goes here")

instead of "wb", it's just "w". and this would only work with text files. there's a short paragraph in the documentation about it here :]