The request is harvesting data from Facebook. For users with a tremendous amount of data, batch requests must be made, so it can take a while sometimes.
I can't say authoritatively for Python, but Twisted is probably what you need here (I have used both Node and EventMachine to do things like this, and I'm pretty sure Twisted is similar). The event reactor model will let you defer the request while it's doing things like performing external IO, so your application is freed up to handle other requests in the meantime.
