For those of us more dictionary oriented, there is <a href="https:&#x2F;&#x2F;pypi.python.org&#x2F;pypi&#x2F;voluptuous" rel="nofollow">https:&#x2F;&#x2F;pypi.python.org&#x2F;pypi&#x2F;voluptuous</a> (which is OK for the most part, as long as you are only trying to do validation, and nothing too crazy)