Old File Purge Suggestions?

[Didjit]

I'm New to Python....

I'm writing a little script to delete old files I back-up daily. I check
todays date w/the file date, if older then X amount of days, remove it.

I'm using sys.stdin.readlines(): getting the date passed in from from "ls -l" (linux). Then
compare dates using the mxDateTime module after shoving dates into a
format I can use. Am I on the right track or is there a better way to accomplish what I need.
Functions or other modulesI should be using.

TIA

Chris