What's the official way of storing settings for Python programs?
As many have said, there is no "offical" way. There are, however, many choices. There was a talk at PyCon this year about many of the available options.
Don't know if this can be considered "official", but it is in standard library: 14.2. ConfigParser — Configuration file parser.
This is, obviously, not an universal solution, though. Just use whatever feels most appropriate to the task, without any necessary complexity (and — especially — Turing-completeness! Think about automatic or GUI configurators).