I'm quoting Larry Wall because he said something interesting.
The comprehensions from twisted were not written for clarity so they aren't good examples. The programmer wanted a one-liner to define these constants.
Asking Larry Wall about good OO/language/library design, or PoLS is like asking George Bush (either really) about effective foreign policy or human rights...
Even if they say something interesting, is it valuable information coming from that source? Should it be trusted?
The comprehensions from twisted were not written for clarity so they aren't good examples. The programmer wanted a one-liner to define these constants.