does anyon want to write an untabify command?

[Skaperen]

i know Linux has a command called "expand" intended to remove tabs. but it doesn't work right. when you run it with a file name, it just outputs the file, without tabs, to stdout, instead of replacing the file (and leaving a backup). and i have no idea what is on Windows or Mac OSX. a pip search comes up empty. does someone want to do this or does everyone want me to do it?