nass is a wrapper around the public API for the USDA National Agricultural Statistics Service.

$ pip install nass

>>> import nass
>>> api = nass.NassApi('your api key')
>>> api.param_values('source_desc')
['CENSUS', 'SURVEY']
>>> q = api.query()
>>> q.filter('commodity_desc', 'CORN').filter('year', 1990)
>>> q.count()
25259
>>> q.execute()
[{'sector_desc': 'CROPS', ...}, ...]

See http://quickstats.nass.usda.gov/ for the full list of fields.

If something goes wrong communicating with NASS, an exception will be raised. This includes connection problems (e.g. timeout, DNS failure), as well as specific error messages.

All exceptions subclass NassException, so you can use it to catch all exceptions.

The full documentation is at https://nass.readthedocs.io.