Schedule file download in Django

How can I order Django App to check for a file (in the link) every day and download it if some conditions are met. Let' say, in a pseudo-code:

every 24h
access link
if filename differs from the name of the existing file (e.g. previously downloaded)  OR there's no such a file 
download file
else skip

I'd be glad for the simplest solution. Maybe a tutorial? Thanks !

PS I want it to be implemented into django app, so please do not suggest using cron