> So as of right now afaik none of the sources of cryptographically
> secure random in the python stdlib offer a way to open a persistent
> FD. The primary question on my mind is if os.urandom can't be modified
> to maintain a persistent FD can Python offer a urandom class that
> *will* maintain a persistent FD?

Well, if we want to offer such a facility, let's bundle it in
os.urandom(). It would be suboptimal to have two slightly different
implementations of the same thing.