[Twisted-Python] fetchmany and deferreds which call back more than once

[andrewextra at puzzling.org]

> On a related item, some database adapters (pypgsql) have
> a non-blocking execute so that you can pool for results
                                         ^^^^
> instead of blocking.  I was wondering how the above
> "producer" mechanism could be used without requiring
> threads (via pooling now and again).
               ^^^^^^^

Do you mean "poll"/"polling"?

-Andrew.