I could use the official python library  but I usually prefer reading away from the computer and then getting back to get some actual work done; so I am looking for a dead-tree book.
Currently I am thinking b/w PER  or PSL by Example . I see that PER gets referred to everywhere but that could also be due to the fact that it came out in 2009 and PSL by Example just came out last month.
On a quick look, it seems PSL by Example gives more of a tutorial feel (which I think is great!) whereby PER is essentially a reference. What would you recommend?
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