I'm not sure what the poststratify does since it's supposed to work with only one column. I'm not sure what it does with two - I'm going to guess it will need to revert to raking.
But the documentation is not clear on this.
https://import-balance.org/api_reference/html/balance.weighting_methods.poststratify.html#balance.weighting_methods.poststratify.poststratify

Vs raking: http://import-balance.org/docs/tutorials/quickstart_rake/

Tasks:

1. Add examples (both in the documentation and tutorial) for post stratify, include one and two features.
2. When using two features, understand what the function does. Does it revert to raking? If so, add warning. If not, clarify in the docs.