Ian Bicking: the old part of his blog

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If you want a concrete example of continuations in Python, you need look no further than Twisted. Essentially, to do anything in Twisted, you need to write code in CPS: continually passing "the next function" to other functions.

peak.events also implements a gentler form of CPS, using generator stacks as continuations, so that you don't have to actually write in CPS.
Comment on Continuations: a concrete approach
by Phillip J. Eby