It's a little convoluted. Seeing as it's a pretty common thing you use when programming computers one might think that there would be a quick and easy method for it. But from what I can tell there isn't. So here is a snippet that will give you a *nix Epoch UTC timestamp.

import datetime
import calendar

now = datetime.datetime.utcnow()
timestamp = calendar.timegm(now.utctimetuple())
print timestamp