Exporting to PDF with a Unique Name

Hello,

I have a script that exports my .mxd to a .pdf and a .png and I would like to add a Unique Name to the exported maps so everytime the script runs the exports don't get overwritten.

I would like to have the date included in the exported documents name. My idea was to add time.asctime() to the title but I can't seem to get that to work.

Any ideas would be very appreciated.

Thanks,
Josh