reading WAL files in python

Hi all. Im having some fun trying to write my own replication system 
using python. I will use the postgres own WAL archiving to write the 
files,  then my app will read them and do some stuff. As im not a C 
programmer, im stuck in the mission of reading the binary files.

I guess im needing to know the internals of how wals archives are, how 
big the buffer has to be, in order to have a complete sql command.

Can someone point some advice?
I was trying to understad src/backend/access/transam/xlog.c, but seems 
too difficult to me :(

Thanks!
Gerardo