lightweight human-readable config?

[Maxim Khesin]

I want to have a config file with my python proggie, satisfying the 
following requirements:
1) support key->(value, default)
2) simple and intuitive to read and edit
3) easyly readable into a python datastructure (a dictionary?)
4) not requiring any heavy libraries needed (I am distributing my 
proggie as a py2exe executable and do not want to bloat the size)

can you guys suggest some format for this? thanks,
max