Setting type codec for whole pool

[Pirulax]

So, the question is how to set the type codec on the whole pool.
I know, that for individual connections, set_type_codec can be used, but I'm not sure about pools.
Also, afaik a function can be specified in create_pool that is called each time a connection is acquired, but that's not too useful because of modularity (as in, I have to set all type codecs in one place, not nice).