[Tutor] How to get script to detect whether a file exists?

[Richard D. Moores]

<http://tutoree7.pastebin.com/0AkVmRVJ> is a work in progress. If I
could get the script to tell whether or not the pickle files already
existed, I could radically revise it (yeah, functions and all :) ). So
how to find if a file exists?

Vista, Python 3.1

Thanks,

Dick Moores