Feb. 10, 2012
2:48 p.m.
Pure python code running in python "threads" on CPython behaves like fibers. I'd like to point out the word "external" in your statement.
I don't believe this to be true. Fibers are not preempted. The GIL is released at regular intervals to allow the effect of preempted switching. Many other behaviours of Python threads are still native thread like, particularly in their interaction with other components and the OS. GIL + Threads = Simplified, non parallel interpreter